Locate the ".Rprofile" file generating default options

Solution 1:

Like @Gsee suggested, ?Startup has all you need. Note that there isn't just the user profile file, but also a site profile file you could have messed with. And that both files can be found in multiple locations.

You could run the following to list existing files on your system among those listed on the page:

candidates <- c( Sys.getenv("R_PROFILE"),
                 file.path(Sys.getenv("R_HOME"), "etc", "Rprofile.site"),
                 Sys.getenv("R_PROFILE_USER"),
                 file.path(getwd(), ".Rprofile") )

Filter(file.exists, candidates)

Note that it should be run on a fresh session, right after your started R, so that getwd() will return the current directory at startup. There is also the tricky possibility that your profile files do modify the current directory at startup, in which case you would have to start a "no-profile" session (run R --no-site-file --no-init-file) before running the code above.