The file “Untitled.rtf” couldn’t be opened. – TextEdit
If you encounter this error, you’ll find various other solutions on the web… But the solution that worked for me was simple: 1. Open System Preferences (click the Apple icon at the top left, then choose System Preferences…) 2. Choose Internet Accounts. 3.  Choose iCloud on the left, then scroll down to Documents & Data. Uncheck it!…Continue Reading…