I upgraded VisualCron from 12.0.2 to 12.1.1 this AM and after which all of my jobs using Job Variables to store UNC paths were throwing and error.

The error was:
Exception in Task: Illegal characters in path.

This happened in tasks like "list files" and "write file" where the 'FOLDER' field was using a Job Variable containing my UNC path.

To debug this, I first create a new job with several tasks to LIST FILES.
1. LIST FILES: hard-coded UNC path - worked
2. LIST FILES: used UNC path in Job Variable e.g. {JOB(Active|Variable|MyUNCPath)} - failed
3. ENVIRONMENT SET VARIABLE - wrote the UNC path to a new var
4. LIST FIELS: using above dynamically written environment variable - failed

I was able to open the task and hover over the FOLDER field and see the value of the Job Variable. It was correct.

I stopped the service, copied my back-up settings files in the /settings/ folder and restarted the service, but i still had the same errors (my new test job didn't exist, so I create a new one).

I ultimately had to install the previous version from the installer for 12.0.2 to resolve my production job issues.

I've not created a support ticket for this yet. Anyone else experience this before?

We are also seeing an issue with the 12.1.1 version upgrade and had to roll the update back. Our job variables also did not seem to be populating correctly after the update, but we also ran into an issue launching the VC application. We were unable to get the VisualCron service to start following the upgrade.

Everything is back to normal for us after rolling the version back and we have not put in a support request either.

Correct, support told us to revert back to 12.0.2 till new version.
Another issue, the client version 12.1.1 will not start after some time anymore.

Version 12.1.2 is out, UNC issues are solved.