After upload my ASP.NET site cannot login to the admin panel - asp.net

Question

i have developed an asp.net web site for university. in visual studio i gave the server hosted sql server database connection string. not the local one. then when i run it on the local host with server hosted sql server database it allows me to log in to the admin panel.
but after i upload the same set of files which use the same server hosted database connection string, when i try to loging using asp.net template login from to my admin panel, it shows follow error. but in the local host the same hosted sql server worked properly.
i used here asp.net configuration to create the admin and only allowed administrator to access administration folder which has all the side administration pages.
please help me to fix this... thank you!!
Error message
Server Error in '/' Application.
A network-related or instance-specific error occurred while
establishing a connection to SQL Server. The server was not found or
was not accessible. Verify that the instance name is correct and that
SQL Server is configured to allow remote connections. (provider: SQL
Network Interfaces, error: 26 - Error Locating Server/Instance
Specified)
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: A
network-related or instance-specific error occurred while establishing
a connection to SQL Server. The server was not found or was not
accessible. Verify that the instance name is correct and that SQL
Server is configured to allow remote connections. (provider: SQL
Network Interfaces, error: 26 - Error Locating Server/Instance
Specified)
Source Error:
An unhandled exception was generated during the execution of the
current web request. Information regarding the origin and location of
the exception can be identified using the exception stack trace below.

Answer 1

Are you using an IP address for your connection? If the database is on the same server as your application you will need to use the home address "127.0.0.1" plus any port configuration you might have. Otherwise it wont find itself.
Same goes if your using a URL connection, you might need to add the URL to the server host file so it redirects back home.
The fact that you can connect from your local dosnt mean anything. Its clearly telling you the problem, your "SERVER" cant connect. Do you have Remote Desktop access? If you can, remote into the server and try connecting to your DB from there.