Video Engine problems in PT 11.3.1

In Pro Tools 11.3.0, the video engine was working fine - I shut down the computer - powered up a few days later and all of a sudden, it doesn't work. It hangs with the message: "Connecting to the Avid Video Engine". I have tried updating to 11.3.1, erasing all PT 10 files, trashing the Prefs, but all to no avail. Do any of you guys have a suggestion?

Thanks in advance :-)