Why do I get a gray screen after launching my Open OnDemand RStudio Server session?

I am attempting to launch an Open OnDemand interactive RStudio Server session on Cheaha. When I do, a new tab opens but I can only see a gray screen. Why is this happening and what can be done about it?

Most commonly, delays in launching Open OnDemand RStudio Server are caused by a large quantities of files referenced in the .rstudio directory in the home directory. This can also commonly occur when a large amount of data was loaded in the workspace in your previous RStudio session. To resolve the issue, you’ll need to locate the hidden directory .rstudio in your $HOME folder. Once you’ve found it, delete it, then try recreating your job.

Warning! Deleting the .rstudio directory will delete the workspace you had open, including any scripts that were unsaved. Saved scripts will be fine.