ASP.NET application breaks when deploying to IIS - asp.net

I am developing a small ASP.NET website for online shopping, when testing it out in Visual Studio, everything works fine, however that is no longer the case when I deploy it to IIS.
The problem seems to be in a DLL file that I reference, this DLL file contains the Classes I need to initialize and send query requests to another server that has all the product information. This DLL was originally a Jar file which I converted to DLL using IKVM.
When I deploy the app to IIS, any page that attempts to instantiate an object defined in that DLL fails with a null reference, for example:
Fulfiller fulfiller = new Fulfiller();
string result = fulfiller.initialize("host", port, "user", "pass");
returns this error:
System.NullReferenceException: Object reference not set to an instance
of an object. at Fulfiller.toLog(String ) at
Fulfiller.initialize(String str1, Int32 i, String str2, String str3)
at Orders.createDataSource()
Now again, this works perfectly on the VS development server but breaks in IIS and I don't know why. Is it some sort of coding problem where the DLL is not loaded properly when running on IIS? or is it a problem with IIS maybe blocking the DLL from executing or sending out requests, I'm very desperate to solve this problem
thanks


Usually, when something that works on the dev sever doesn't work on IIS, the problem is authorizations (the VS server runs under your credentials, but IIS runs as "Network Service" or another system user).
For example, I see your code breaks on fulfiller.toLog().
Could it be that the toLog() function is trying to open a log file and that the user impersonated by IIS is not authorized to read or write it?


What is fulfiller.Initialize() doing? Can you post that code?
Clearly you have a fulfiller reference, because you can't pass the constructor without error and then have a null-ref.


I second Loris' answer.
The dev server has your permissions. Assuming you are deploying to Windows Server, or any machine running Active Directory, you should be able to right-click on the directory where the log files are stored and select properties. In the dialog box, there will be a tab labeled Security. If the Network Service user (or IUSR_machinename) is not visible, you will have to add them to the list. Select the user and assign them read and write permissions.
Do not give the IIS user full permissions to your entire application directory. It is a huge security vulnerability, hence the default deployment not giving you the permissions that you currently need.


I have not used IKVM, but I am sure that some IKVM runtime must be installed on the server. Have you checked IKVM on the server?
Hope this helps.

Related

ASP.NET Core - Application not connecting to database after publishing

I created a simple ASP.Net Core application with user authentication (so all the Entity Framework has been preloaded into the web app template). It is connecting to my database with the connectionString that is located in my appsettings.json file, with "data source = {computerName}\\{serverName}" setup.
The database instance and Visual Studio are located on the same machine. This works fine in returning data to the web api while within development and debugging mode. When I publish it and try to go to the site from a domain name it does allow me to view the webpages that are not needing database connection but the rest that need data from the database returns pages like this:
Error.
An error occurred while processing your request.
Development Mode
Swapping to Development environment will display more detailed information about the error that occurred.
Development environment should not be enabled in deployed
applications, as it can result in sensitive information from
exceptions being displayed to end users. For local debugging,
development environment can be enabled by setting the
ASPNETCORE_ENVIRONMENT environment variable to Development, and
restarting the application.
I have tried to change the Environment Variables for ASPNETCORE_ENVIRONMENT from Development to Production to no success.
I have tried adding appsettings.Production.json to publishOptions in my project.json file, even though there is no file appsettings.Production.json, and this did not help. dotnet publish
Adding the evironment variable in the web.config file did not work Deployment
I need help getting the published web api to connect to my SQL Server database from outside the development Visual Studio setup.
The last thing I can think of is that maybe I am incorrect in how I understand the connection string. If the web api uses the connection string to connect to the database from the server-side then it should work just fine like it does when in development calling to http://localhost:port# since it's all on the same machine. But, if the database string needs to be based on a client-side call then it would have to be with domain names and IP addresses.
Can someone tell me which one it is?
The only thing else that comes to mind is that there is something I am not doing, and need to do, inside of IIS Manager. I see connect string there as well but unsure what that is for our does since the connection string is inside the application. Also maybe I am suppose to give the app some kind of authorization to communicate with the database server even though they are on the same machine???

After much research, finally googling "how to deploy a web api in iis" I was able to learn from Host ASP.NET Web API in IIS using Visual Studio Publish that I needed to add the security entity BUILTIN\IIS_IUSRS. Then placing a mapping to my database tables and giving db_datareader (and possibly db_datawriter) for the database to the IUSER to allow access from my self hosted IIS web api. This from the above mentioned link with the part stating
Accessing Database under IIS APPPOOL\ASP.NET v4.0
As we are using ASP.NET v4.0 App Pool make sure IIS APPPOOL\ASP.NET v4.0 is added to your Database Server -> Security -> Logins.

Can't Access SQLite DB on Azure Web App

I have created an ASP.NET MVC web app which uses an SQLite database under EF6.
The app works fine in VS. The database is included in the project in the App_Data folder. When I publish to Azure (or an IIS test server on the LAN) I get an error. The Azure instance is showing an HTTP 500 error, and it only happens on views which require database access to load. Other than that it works fine. The IIS test server shows an error saying unable to open database file. I tried loosening file permissions on the .db file on the IIS instance, but nothing changed. I'm not sure how to go about doing anything on the Azure instance.
Can someone please assist me with debugging a SQLite connection problem on Azure/IIS?
Details
VS 2015 Enterprise
Azure app services (free tier, production server)
SQLite3 database
IIS on Windows Server 2012R2 (test server)
I have tried all sorts of combinations of connection strings:
setting a connection string to the D:/xxx/xxx path in Azure Portal
modifying the connection string in the deployment profile in VS (replaces value in web.config upon deployment)
just leaving it all the same
Nothing has worked or even changed the error. Perhaps one of those configurations is able to access the file but simply can't open it (which is sort of what the IIS error suggests, I think). Even then, how do I go about finding out?
EDIT
On the IIS test server I discovered that the entire problem was that the connection string in Web.config was wrong. I manually edited it on the server and it fired right up. I'm still not sure how to correct the path on the Azure server, nor how to correct my deployment settings in VS to inject the correct path. Thoughts along those lines are still appreciated.
EDIT 2
I've also found that each time I hit a page requiring DB access, I see this error show up in the application logs on Azure:
2017-01-03T20:25:32
System.ApplicationException: The trace listener AzureBlobTraceListener is disabled. ---> System.InvalidOperationException: The SAS URL for the cloud storage account is not specified. Use the environment variable 'DIAGNOSTICS_AZUREBLOBCONTAINERSASURL' to define it.
at Microsoft.WindowsAzure.WebSites.Diagnostics.AzureBlobTraceListener.RefreshConfig()
--- End of inner exception stack trace ---

After some abysmally slow debugging sessions, I finally remembered that in toying around I had set a connection string value in the Azure portal.
Apparently whatever value is set in the Azure Portal overrides (at runtime?) the values in the Web.config file
I simply deleted the connection string from the Azure Portal (your app/Application Settings/Connection Strings) and it worked. The final connection string looks like this:
<add name="yourThingEntities" connectionString="metadata=res://*/cadb_SQLite.csdl|res://*/cadb_SQLite.ssdl|res://*/cadb_SQLite.msl;provider=System.Data.SQLite.EF6;provider connection string="data source=D:\home\site\wwwroot\App_Data\yourSQLiteDBFile.db"" providerName="System.Data.EntityClient" />
To get the Web Deploy working in VS, you'll need to edit the publish profile to have a connection string matching the format
data source=D:\home\site\wwwroot\App_Data\yourSQLiteDBFile.db
Apparently not many people use SQLite for web apps, and most people should not. If you ever expect more than one user for your website at a time, you shouldn't fix SQLite, you should convert to SQL Server CE or just full-blown SQL Server which Azure will take care of for a paltry $5/mo. Choose wisely!

How do I grant unmanaged DLL with WRITE permission on files using fopen in ASP.NET web service?

I wrote an XML Web Service that run with an unmanaged dll which creates a file for writing.
But when my unmanaged dll tries to use _wfopen to WRITE something into an existing file, it causes a security issue: ACCESS DENIED!! And then _wfopen receives a NULL back.
I originally used _wfopen with r+b to access file. To test the permissions it had,
I tried to change it to use rb (Read file only), then the file opened successfully. This means I can access the file with READ access.
I also found that directly accessing the file through C# code does not cause this problem.
(e.g. if I use File.Create etc.).
The OS I'm running is WinXP Professional SP3 with IIS 5.1. So there should not be directories or files permissions not set properly in such a system.
Is there a way to solve this problem?

After lots of Code Fighting, I came to a conclusion: THIS MAY NOT BE A CODE PERMISSION ISSUE.
So I tried to configure my web service in IIS.
I finally found that configuring the ASP.NET tab of the property page can solve this problem.
On the ASP.NET configuration page, I go to the Application tab and check Impersonate in Identity Settings, and input username/password with my computer login data.
After that, everything went well and the problem was solved.
I hope this helps for those who have the same problem as me.
Thanks for any advice!

HTTP Error 503, the service is unavailable

I'm really new to setting up web servers in general. I've got IIS 8 on Windows 8, and I'm trying to set up a little site locally, while doing some development. In IIS I choose Add Site, give a name, points to a location where I have a index.html file (I've tried different locations, latest in a c:\inetpub\wwwroot\test -folder) and otherwise use all default settings. However, when I try to browse to localhost I get
HTTP Error 503. The service is unavailable.
I've verified the pool is started, and I've given IIS_IUSRS Full Control on the target folder
I've search around but not found anything that solved my issue, and there's nothing helpfull in the EventLog or in the C:\Windows\System32\LogFiles\HTTPERR folder
Could anyone tell me what's wrong?

It could be that the user identity is outdated, especially if you've tried starting a stopped app pool and the next request again fails.
In IIS, go to the Application Pools under the Server, then find the correct Application Pool for your web site, and click on it. On the Advanced Settings menu to the right, select Identity and change it and enter new user and password. Click on your Application Pool again, and select Recycle to restart it.
You can also try looking at the error message in Event Viewer, under Windows Logs, Application, Details tab.

Other answers are fine. But in my case, I was working on a Windows box that already was running some old IIS, IISExpress or any other web site. What happened is urls ACLs where reserved somehow in the system. So, you might want to check this.
Here is the console command to dump all URL acls:
netsh http show urlacl
Check what's returned here, and if anything matches the url you are testing, here is the command to delete one URL acl (for example):
netsh http delete urlacl url=http://localhost:2018/
(beware to carefully note what you do here in case it was not related to the original problem)

In my case the problem was the DefaultAppPool. I changed the "Load User Profile" to false and now it works. However, I don't know if there are side effects to this.
Further reading on setting the Load User Profile option: What exactly happens when I set LoadUserProfile of IIS pool?

Check your application's respective Application Framework Pool - it could be stopped. If it is, start it and check again.
If you're still experiencing issues you can also check out Event Viewer to find the cause of that error in order to troubleshoot more.

If the app pool is running under some specific user identity, then go to the advanced settings and update the username and password again to ensure they are correct.

If the app pool immediately stops after you start it and your event log shows:
The worker process for application pool 'APP_POOL_NAME' encountered an
error 'Cannot read configuration file ' trying to read configuration
data from file '\?\', line number '0'. The data field contains
the error code.
... you may experiencing a bug that was apparently introduced in the Windows 10 Fall Creators Update and/or .Net Framework v4.7.1. It can be resolved via the following workaround steps, which are from this answer to the related question Cannot read configuration file ' trying to read configuration data from file '\\?\<EMPTY>', line number '0'.
Go to the drive your IIS is installed on, eg. C:\inetpub\temp\appPools\
Delete the directory (or virtual directory) with the same name as your app pool.
Recycle/Start your app pool again.
I have reported this bug to Microsoft by creating the following issue on the dotnet GitHub repo: After installing 4.7.1, IIS AppPool stops with "Cannot read configuration file".
EDIT
Microsoft responded that this is a known issue with the Windows setup process for the Fall Creators Update and was documented in KB 4050891, Web applications return HTTP Error 503 and WAS event 5189 on Windows 10 Version 1709 (Fall Creators Update). That article provides the following workaround procedure, which is similar to the one above. However, note that it will recycle all app pools regardless of whether they are affected by the issue.
Open a Windows PowerShell window by using the Run as administrator
option.
Run the following commands:
Stop-Service -Force WAS
Remove-Item -Recurse -Force C:\inetpub\temp\appPools\*
Start-Service W3SVC

Or if none of the current solutions work, look in your website's directory for a file called app_offline.htm. That basically tells IIS that your site is unavailable and to show this page instead.
To fix it, either delete it or rename it to app_offline.htm.bak.
In my case, I added it while showing a colleague how to use that to prevent traffic to the site temporarily and then forgot that I did that on my box. Sigh.

Start by looking in Event Viewer, either under the System or the Application log.
In my case the problem was that no worker process could be started for the App Pool because its configuration file couldn't be read - I had included an extra '.' at the end of its name.

I resolved this issue by removing a URL reservation that matched my app directory in IIS. I had a similar (definitely not the same) issue as outlined in this article:
A Not So Common Root Cause for 503 Service Unavailable

It is possible that your domain requires the account used for running the AppPool to have batch logon rights. In which case you will see this same error message. The way you can tell if that is the case, is by looking at the System events in the Event Viewer. There should be an event saying that the account being used with the App Pool has either 'the wrong password or does not have batch logon rights'.
This is why developers quite often use IIS Express on their development machine, since it by passes the batch logon rights issue.

I ran into the same issue, but it was an issue with the actual site settings in IIS.
Select Advanced Settings... for your site/application and then look at the Enabled Protocols value. For whatever reson the value was blank for my site and caused the following error:
HTTP Error 503. The service is unavailable.
The fix was to add in http and select OK. The site was then functional again.

For my case, My Default Application Pool was offline.
To troubleshoot the problem, I checked the IIS logs located in C:\Windows\System32\LogFile\HTTPERR. Scroll down to the most recent error logs, this will show you problems with IIS if any.
My Error was "503 1 AppOffline DefaultPool"
Solution
Open IIS Manager
Click on Application Pools, this lists all application pool to your right.
Check if the application pools hosting your api or site has a stop sign on it. If so, right click the application pool and click start.
Try again to access your service from the client

Check Event Viewer - Windows - Application. If there is a red Error line made from IIS-W3SVC-WP and the message is like The Module DLL C:\Windows\system32\inetsrv\rewrite.dll failed to load. The data is the error. then you are missing some Windows Setup features.
In Windows Server 2012 go to Server Manager, Add Roles and Features, Web Server (IIS) and add the matching feature. Usually, most of the Application Development section is installed. Here is a complete list of IIS features and their associated DLL to help in diagnosis.
After going through a few iterations of that I ended on the error message above regarding "rewrite.dll". This led to a direct download and install of Microsoft URL Rewrite tool. Finally all websites came to life.

Our server ran out of disk space on Sunday afternoon which led to an application suddenly failing and returning HTTP error 502. The logs were empty so it had to be something that was occurring before IIS even did anything.
A swift look at the event viewer(WIN+R > eventvwr) exposed the issue.
It's a good idea to filter out the output of the System and Application windows to WAS since it can get pretty verbose in there.
The application depended on another one which was disabled. Therefore keep in mind an application can go down indirectly if one of it's dependent processes has gone down. We simply re-enabled the .NET application pool and our other application started running normally again.

If you have IIS URL Rewriting installed it could be to do with that. I suffered issues after a Windows 10 Update.
This StackOverflow post helped me.
Go to Windows Control Panel > Programs and Features > IIS URL Rewrite Module 2 > Repair.

i see this error after install url rewrite module i try to install previous version of it from:
https://www.microsoft.com/en-us/download/details.aspx?id=7435
it fixed my error

In my case, the problem was that another application was using the port that I had bound to my web site.
I found it by running the following command from a command line, which lists all of the listening ports and the executable involved:
netstat -b

If you have McAfee HIPS and if you see the following error in event viewer application log:
The Module DLL C:\Windows\System32\inetsrv\HipIISEngineStub.dll failed to load.
The data is the error.
Then this workaround on McAfee.com resolved the issue in my case.
Quote from the page:
Click Start, Run, type explorer and click OK.
Navigate to: %windir%\system32\inetsrv\config
Open the file applicationHost.config as Administrator for editing in Notepad.
Edit the <globalModules> section and remove the following line:
<add name="MfeEngine" image="%windir%\System32\inetsrv\HipIISEngineStub.dll" />
Edit the <modules> section and remove the following line:
<add name="MfeEngine" />
After you have finished editing the applicationHost.config file, save the file, then restart the IIS server using iisreset or by restarting the system.

Actually, in my case https://localhost was working, but http://localhost gave a HTTP 503 Internal server error. Changing the Binding of Default Web Site in IIS to use the hostname localhost instead of a blank host name.
tname for http binding

This could also happen if any recent installs or updates happened with .NET framework and/or ASP.NET. If you are unsure of what happened recently and if all your apps use ASP.NET version 4, you can try reset them by running the following commands in command prompt in administrator mode.
cd C:\Windows\Microsoft.NET\Framework64\v4.0.30319
aspnet_regiis -i
This makes sure to install or reinstall ASP.NET 4 and updates existing applications to use ASP.NET 4 version of the app pool. It updates both IIS Classic and Integrated mode handlers and script mappings in the IIS metabase. It also recreates ASP.NET v4.0 and ASP.NET v4.0 Classic app pools, and sets .NET framework 4 to DefaultAppPool and Classic .NET app pools.

I changed the port from 80 to 8080, that's why this error occur. I write localhost/ in search bar then this error occur. My problem is resolved by writing localhost:8080/ in the search then local host open.

This happened to me on a server on our intranet. After browsing through blog posts and Windows logs, it turned out that a few days before Christmas 2015 (related to a Windows Update?) my web site application pool wanted to create a config file in folder c:\inetpub\temp\appPools, but access to this folder was restricted. This caused the application pool to be disabled.
After adding Full control to Everyone on this temp folder, I restarted the Windows Process Activation Service and everything went online again.
If I'd been a little more elegant, it would probably had been enough to grant the AppPool user full control to the folder, but I never seem to remember how the app pool name and app pool user relates to eachother...

Same thing with IIS Express 10.0 after upgrading Windows 7 to Windows 10.
Solution: go to IIS and enable all disabled websites and reinstall ASP.NET Core.

Also check the address bar and make sure the page is in the right location.
This error can be returned instead of the 404 (Page not found). In my case, it was a bad link on the page that didn't have a subfolder included.

I was having this problem when cleaning up my IIS on dev machine, and I had somehow created a virtual folder for a subfolder of my actual development web that I couldn't clear and was creating conflicts.
To clear it I had to use
C:\Windows\System32\inetsrv\appcmd.exe list vdir
and then individually remove the problem virtual directories using
C:\Windows\System32\inetsrv\appcmd.exe delete app /app.name:"Default Web Site"/{name of virtual directory}

For me the solution is to change Enable 32-bit Applications to False
None of the answers worked for me. So I'd like to share what I found after hours of research..
Keep seeing this message from event logs: The Module DLL C:\Windows\system32\RpcProxy\RpcProxy.dll failed to load. The data is the error. Turns out that dll is 64bit and cannot be loaded into 32bit process.

You can also try the following.
Right-click on the site and 'Basic Settings...'
Click on 'Connect As...'
Click on Specific User and give the new credentials.
Now it should work.

In my case, I had to change my userPass of network because company policies. So, you need to edit your AppPool:
click on Application Pools. Select your pool, 'advanced Settings...' go to 'Process Model' click on 'Identity' and Click on Specific User and give the new credentials.

This might be because of number of connections to the database. I had such a situation and so, wrote a de-constructor and killed db open connection and it resolved.

I had the same problem and found it was caused by permission problems creating the user profile in C:\Users. I gave ApplicationPoolIdentity full permissions to the C:\Users folder, started the site and everything worked, the profile must have been created properly, and my site worked as it should. I then removed access to C:\Users from ApplicationPoolIdentity.
Site wont start on local using ApplicationPoolIdentity, only when using NetworkService: "HTTP Error 503. The service is unavailable."

Classic ASP suddenly giving me permissions (401.3) error

Background: I support a classic ASP environment. I have a development setup locally on my machine as part of that support. I am running IIS7.
To access my environment, I use "http://localhost:99999/" (port # faked for privacy purposes). I have not had a problem with this -- until today.
I built an application that is intended to run in this environment. The app is ASP.NET v.4.0 (for sake of example, I'll say it's called "http://localhost:99999/DotNetApp/"). Of course, in order to run this, I had to set up my environment application pool to support it (which it now does).
Problem: after configuring this, I am now getting:
Server Error in '/' Application.
Access is denied.
Description: An error occurred while accessing the resources required to serve this request. You might not have permission to view the requested resources.
Error message 401.3: You do not have permission to view this directory or page using the credentials you supplied (access denied due to Access Control Lists). Ask the Web server's administrator to give you access to '[filepath]\SourceFiles'.
I did NOT get this before I set my IIS configuration. Why am I getting this now?
Note: this ONLY happens with "http://localhost:99999/"; this does NOT happen if I try "http://localhost:99999/default.asp" (the page comes up with no problem).
Anyone have any insight?
Thanks in advance . . .
Edit: Additional symptoms: I tried playing with the application pool settings. The problem goes away if I change the .NET Framework version to either 2.0.50727 or to "No Managed Code." Changing it to 4.0.31319 breaks it. Of course, if I use any of the other two versions, my ASP.NET app won't run.
Edit #2: This problem occurs on ALL links that go to a folder or directory (e.g. "http://localhost:99999/somefolder/"), not just the web root.
Edit #3: I have a workaround: set "http://localhost:99999/" and "http://localhost:99999/DotNetApp/" in separate application pools. The first runs in .NET 2.0, while the latter runs .NET 4.0. (I'll post this as an answer once my 8 hour limit is up.) Probably not the best answer -- I'd prefer something that isn't as much of a kludge -- but for the time being, it'll get the job done. However, if anyone has a solution that enables me to run everything in the same app pool, by all means, post away!

You probably must specify "default.asp" as allowed in your "Default Document" settings in IIS7
EDIT: Check if ASP has been installed: Control Panel -> Programs and features -> Windows Features -> Internet Information Services -> Www services ->Application Development Features-> ASP
EDIT Final solution: The IUSR account is missing from the folder the website is in.

Set the default page for your site in IIS.

Try to set permission "Everyone" for directory "[filepath]\SourceFiles/" or/and "Allow" for other user names and groups in folder properties.

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