I generally use my own account to create and publish workflows. One day, none of my workflows were completing and they were all stuck on “starting”. I thought maybe there was something wrong with the workflows themselves so I tweaked one of them a bit and re-published and voila! It worked! But the thing I tweaked really shouldn’t have “fixed” anything. So I changed it back and again, it worked!
After banging my head against my desk for a little while I remembered updating my password that morning. Maybe all I needed to do was republish my workflows.
Which is what I did and it fixed everything.
There may have been an easier solution, but this worked for me.
If you’re going to use your own account to create and publish workflows, you might have to re-publish every time you change your password.
You should probably use an admin account without a password policy to publish workflows.