epcior:
Hi,
My IDE was also slow and freezing at startup, compile, open, close and upload.
My solution was to simply uninstall Arduino IDE and manually delete one of the folders suggested by Ballscrewbob that was full of garbage (>1.5GB :o ):
C:\Users\yourname\AppData\Local\Arduino15 depends on IDE
Of course, after this, reinstall Arduino IDE!Hope it helps.
this is finally worked for me !thank you!