When upgraded to the v9.12.5 the workflows are not functioning. What is the cause?

[smamidi7]

[Matt Parks]

It looks like there is a workflow validator on that transition which is failing. Can you provide more detail around the validator? If it is a scripted validator, please include the script.

I'm assuming that you upgraded from an 8.x release. I had a similar problem where certain classes had been deprecated which caused my scripts to fail. Fortunately, someone had run into a similar issue and already posted a solution which worked, so I didn't have to write something from scratch.