Yes. I've had Media Encoder hang on me at least three times in the past week. Had to quit ME, then force quite a BG-procerss of After Effects. After that i was able to restart Media Encoder and the render would finish.
Well I can only speak for Media Encoder as I don't render with AE.
In ME stop the render and close the app. Then, if you're on WIndows, open the task manager and in the processes tab look for an instance of AE running as a background process, right click on it and end the process. After that you should be able to re-open media encoder and execute the render. At least that's what works for me.
If you don't see an instance of AE running or, if you're on an apple OS & cannot figure out how to force quit a background process then reboot your computer and see if that helps.