Package install issues (error message: unable to access index for repository)

Hello. I am trying to install a few packages for running a program, and error messages as below occur, hindering me from installing the packages.
I am using a Windows 11 OS, and R-4.4.1, would be appreciated for any advice to solve this issue.

(original code) >> if (!require("tidyverse")) install.packages("tidyverse")

(error message below)

Loading required package: tidyverse
Warning in install.packages :
unable to access index for repository
cannot open URL ''
Warning in install.packages :
package ‘tidyverse’ is not available for this version of R

A version of this package for your version of R might be available elsewhere,
see the ideas at

Can you access that PACKAGES URL from your browser?

Are you behind a proxy?

Yes, I can assess the "packages" URL from by browser.

I am using Rstudio from my company-provided PC, how can I check if I am behind a proxy?