I installed the newest version of R over the weekend from version "3.6" to "4.0.3". Since I have updated the newest version I cannot call in libraries or import non-csv files (such as Excel) using "library()". Below is the error message I receive: "Error: package or namespace load failed for ‘readxl’ in readRDS(nsInfoFilePath): unknown input format", and I encounter the same error for other packages (such as dplyr and ggplot2). Last week I had no problems knitting an RMarkdown file and now I encounter an error of "Error in readRDS(ffile) : unknown input format Calls: :: ... loadNamespace -> namespaceImport -> loadNamespace -> readRDS Execution halted".
I've tried uninstalling R and RStudio completely and reinstalling which has encountered the same error. I've looked in previous discussions for any way to fix this issue, and all have been without success. Any thoughts on how to fix it would be greatly appreciated!