any thoughts on how to fix this?
Reinstall is all I can suggest.
If you haven’t already, close and reopen the app
tried that and it did not work
I’ve had this issue for a while too (ever since my laptop’s hard drive started corrupting and I had to replace it with a SSD), I managed to get it to work for a little bit after uninstalling everything with Revo uninstaller but it went right back to not working again after I started rendering something in studio.
One piece of advice can give though: you can get partial functionality back by clicking on one of the sample models on the startup window, attempting to close partdesigner, and then pressing cancel on the “are you sure you want to quit?” window.
You won’t be able to import parts from studio or put printings on anything other than minifig heads and flat tiles, but it’s something at least.