R-Version 4.5.1: caret not available for this R version

[lazaricl]

I am using caret in a Markdown and have updated my R recently for another package (mxsem). However, I cannot install caret (also not able to include pROC on a side note). the following error message comes up:

Warning in install.packages :
unable to access index for repository https://cran.rstudio.com/src/contrib:
cannot open URL 'https://cran.rstudio.com/src/contrib/PACKAGES'

Warning in install.packages :
unable to access index for repository https://cran.rstudio.com/src/contrib:
cannot open URL 'https://cran.rstudio.com/src/contrib/PACKAGES'
Warning in install.packages :
package ‘caret’ 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
https://cran.r-project.org/doc/manuals/r-patched/R-admin.html#Installing-packages
Warning in install.packages :
unable to access index for repository https://cran.rstudio.com/bin/windows/contrib/4.5:
cannot open URL 'https://cran.rstudio.com/bin/windows/contrib/4.5/PACKAGES'