JBlazar

I tried that earlier. It found corrupted files but was unable to fix them. From the link you gave me, I ran DISM and it went fine. Then I ran sfc, but got "Windows Resource Protection could not start the repair service", even after running chkdsk. I guess this is more of a system issue than a paint.net issue, huh?

Hi, sorry to bother anyone with another (null) error, but after reading through older posts and trying their suggestions, I've resorted to posting my own. I've already tried the PdnRepair.exe, but when I restart my PC after it asked me to, the error message still shows up. I've also tried the .NET Framework repair tool, but nothing happens after reinstalling Paint.NET. And running the setup for 4.8 gives me a message saying that it's already installed. There's also this link, but it won't let me download the troubleshooter (404 Not Found). If anyone can help me, that would be great. Thanks!