Also no. I work from home, and I have my own wifi-network setup. No firewall there. I've checked with my internet provider if they have some sort of security settings active, but that's also not the case.
Okay, maybe try this:
1. Close XD and all other Adobe applications
2. Sign out and then quit the Creative Cloud desktop application
3. Open the Activity Monitor (Applications -> Utilities -> Activity Monitor on Mac) or the Task Manager (Windows)
4. Force quit the following processes (to force quit, select the process from the list and click the force quit button):
5. Navigate to the OOBE folder:
6. You will see a file named opm.db in the OOBE folder. Rename that file to opm_old.db
7. Launch the Creative Cloud Desktop application and sign in with your Adobe account
8. Launch Adobe XD and attempt to share
-Elaine