Cannot install packages in Rstudio

Question

I just installed R studio and I was trying to install rmarkdown. However, I got the error as below. I unchecked the box ''Tools -> Global Options -> Packages -> Use secure download method for HTTP'' as someone suggested. No help. I tried other packages, I got the same error.

Answer 1

You should remove the package and reinstall it using dependencies = TRUE :

 remove.packages("rmarkdown") install.packages("rmarkdown", dependencies = TRUE) library(rmarkdown)

Output:

 Warning message: package 'rmarkdown' was built under R version 4.1.2

Answer 2

I had the same issue and it was due to the newest version of the toolboxes include the names is under new package names. Go to the URL https://cran.rstudio.com/src/contrib/PACKAGES and search for "rmarkdown". Find the package name and try to install that instead. It's like a.zip file that includes several packages to your library. Try install.packages("accucor"). It worked for me at least, and then try to install the rmarkdown package.