When I launch Pr, ALL my projects disappear!

[Robert27987075jf5j]

Since 2020, I've been running Pr on my Dell Latitude 7290 laptop running Windows 10.  This glitch just began a week ago. When I launch Pr, all my projects are visible, BUT as soon as I click on any of them, they ALL disappear, and my library becomes one big black screen. The top of the screen still shows that I'm in Pr, with the normal headings (File, Edit, Clip, Sequence, View, Help) but everything below that is black. 

Today I un-installed and re-installed Pr, but the same issue persists. My C-drive has 15Gb free out of 237Gb. What can I do?  

[Myra Ferguson]

Are you signed in? If not, then it won't sync your projects. You can check in Premiere Rush (Ru -- Pr is Premiere Pro) by going to the Help menu to see if you're signed in. Also check that you're signed into the Creative Cloud Desktop app.

[Robert27987075jf5j]

As suggested, I signed out and signed back into CC Desktop.  Problem persists. All my projects show up on screen upon launching Ru, but as soon as I click on any project, they ALL vanish and my project library goes black.