I spent 3 days last week working with a technician to uninstall and re-install my .NET framework and then run a .NET cleanup tool to get security updates to install. Now when I try to open any of about 60 paint.net files that I was working on during those 3 days I receive the message “There was an error opening the file.” There are, however, 3 files I opened or created during this period that do open and for which I receive no message. I don’t seem to have any trouble with any files created before or after these 3 days. Could the re-installation of the .NET framework be the trouble with these files? Is there something I can do to get these files to open again?