Hello, I have a case where Acrobat is asking for a new name and location for an existing file when you want to save changes after editing. It says it must be open elsewhere while there is no other. I have cancelled protected mode as well as thrid party add-ins but none has helped. Also, Acrobat is up to date!
Hope you are doing well and sorry for the trouble. As described, after editing the PDF its asking for new name and location for an existing file when you want to save changes. Also you have tried cancelling the protected mode and third party add ins with no success.
Would you mind sharing the version of the Adobe Acrobat DC you are using? To check the version go to Help > About Acrobat and make sure you have the latest version 21.01.20155 installed. Go to Help > Check for Updates
Also, please try the steps as mentioned:
Go to Edit (Windows), Adobe Acrobat (Mac) > preferences > Enhanced Security > Uncheck 'Enable Protected mode at startup' > Click OK and reboot the computer once.
Note: Please turn on the security after testing to avoid any security risks.