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Click and drag the Library folder into the 4.1.3 folder. (You may select skip or replace for file existing files).
If you have not yet opened RStudio, you will need to create the 4.1.3 folder.
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Doing this will change the folder in which RStudio loads your library, as shown above, if you select 4.3.3, the library path will be P:\%USERNAME%\AppData\Roaming\R\4.3.3\Library
Additional steps/notes:
How can I tell which version of R I am using?
When loading RStudio, you will see at the top of the console:
If holding CTRL on your keyboard does not load the "Choose R Installation" Please search for the On-Screen Keyboard within Windows start menu, and use this. Pressing the Windows Key on your keyboard, or clicking the menu on the Desktop, type "On-Screen Keyboard"
Related issues, but not strictly required:
"Unable to install packages" This is likely due to the proxy not being set, to set correct this add the following into the R Console:
Sys.setenv(http_proxy="http://proxy:8080)
Sys.setenv(https_proxy="http://proxy:8080)
RStudio error with package and R version
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