Hi there,
We're so sorry to hear about the trouble. Please try the steps shared below:
- Sign out of XD and Creative Cloud Desktop app.
- Close CoreSync and All Adobe related processess from the Task Manager/Activity Monitor.
- Reboot the computer.
- Sign back in on the Adobe CC Desktop app and launch XD from there.
- Let us know if you are able to save the file.
If it still doesn't work, please share a screenshot of the About XD info page under the XD menu option on the macOS and under the Help menu option on Windows. Also is it happening with a specific file or multiple files?
Regards
Rishabh