Whenever I try to do anything in Rstudio (Ex. Use R Markdown, install any packages, create a project) I receive the "Unable to establish connection with R session" popup. I know R works, as I can do codes in it, but I cannot replicate them in Rstudio. I have uninstalled and reinstalled, tried older versions, and made sure I had R installed before installing Rstudio. What else should I try?
First, try this, it's my new go to suggestion for anyone with weird R Studio behavior,
After that, the art of asking for help is, in fact an art. There are so many variables present in a modern computer it's impossible for anyone to know which combination of a thousand possible things could be the culprit when something like this happens. So the more information you give the better.
Here are a few things off the top of my head which might help the right person know how to help you better:
What operating system are you using?
What version of R Studio?
What version of R?
Does the interface load completely, partially, or not at all?
When you open R Studio is it trying to load a project, restore a workspace, or is it a clean open?
Did R Studio perviously work without issue on the same machine?
Have you tried rebooting your computer?
How did you install R Studio? Download it from the website or with some kind of package manager?
Did you install any other software between the last time R Studio worked and now? What was it?
Is your system a multi-user system? That is are there other user accounts on it and does R Studio work for any of them?
Have you edited any of the R Studio configuration files recently (or ever).
When you installed the software (R and/or R Studio) did you install it in the default location or did you point out to somewhere else?