How can I install readxl package for R? - r

Question

I am trying to install readxl package for R.
The following is the RStudio output:
To learn more and/or disable this warning message see the "Use secure download method for HTTP" option in Tools -> Global Options -> Packages.
> library('readxl')
Error in library("readxl") : there is no package called ‘readxl’
> install.packages("readxl")
Warning in install.packages :
unable to access index for repository http://cran.rstudio.com/src/contrib:
cannot open URL 'http://cran.rstudio.com/src/contrib/PACKAGES'
Installing package into ‘C:/Users/Lenovo/Documents/R/win-library/3.5’
(as ‘lib’ is unspecified)
Warning in install.packages :
unable to access index for repository http://cran.rstudio.com/src/contrib:
cannot open URL 'http://cran.rstudio.com/src/contrib/PACKAGES'
Warning in install.packages :
package ‘readxl’ is not available (for R version 3.5.0)
Warning in install.packages :
unable to access index for repository http://cran.rstudio.com/bin/windows/contrib/3.5:
cannot open URL 'http://cran.rstudio.com/bin/windows/contrib/3.5/PACKAGES'
>
The following is the R's console output:
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> install.packages("readxl")
Installing package into ‘C:/Users/Lenovo/Documents/R/win-library/3.5’
(as ‘lib’ is unspecified)
--- Please select a CRAN mirror for use in this session ---
Warning: failed to download mirrors file (cannot open URL 'https://cran.r-project.org/CRAN_mirrors.csv'); using local file 'C:/PROGRA~1/R/R-35~1.0/doc/CRAN_mirrors.csv'
Warning: unable to access index for repository https://cloud.r-project.org/src/contrib:
cannot open URL 'https://cloud.r-project.org/src/contrib/PACKAGES'
Warning: unable to access index for repository https://cloud.r-project.org/bin/windows/contrib/3.5:
cannot open URL 'https://cloud.r-project.org/bin/windows/contrib/3.5/PACKAGES'
Warning messages:
1: In download.file(url, destfile = f, quiet = TRUE) :
InternetOpenUrl failed: ''
2: package ‘readxl’ is not available (for R version 3.5.0)
>
How can I solve this issue?

Answer 1

The error messages definitely seem to be telling you, that R cannot connect to download the packages. Here are some thoughts:
Does your user profile have administrative privileges? I am not a huge Windows user, but your are technically trying to add software, which sometimes requires escalated privileges. Maybe trying running R as Admin in windows, for this one issue to see if that is the problem. (Doesn't seem very likely.)
If it is a firewall issue you could try to add an exception to your firewall settings for R and/or Cran repositories.
Have your tried to account for dependent packages? install.packages("readxl", dependencies = TRUE) (This can cause its own bag of issues as well, so consider yourself forewarned.)
Can you download any other packages? As you can access the internet to make stack posts, are asking a fairly entry level question, and the URL's are valid so there may be a configuration issue with your installation of R. If all else fails, you may wish to uninstall/reinstall R on your system (and Maybe R studio while you are at it) as that may help to repair something if it is damaged. Use the file checksums, the are there for a reason.