Hey all,
Upgraded AE, Premiere Pro and MediaEncoder today (Apr 4, 2018) to latest version and got the above issues. After trying most of the stuff above - nothing helped.
Then i noticed that MediaEncoder behaves same way as AE and PP. It must be the graphic drivers!
I'm on win7, so i upgraded Nvidia drivers and ... no change at all.
Then in nVidias Control panel-> 3d settings for programs -> set the AE, PP and MediaEncoder to use integrated graphics instead of default nVidia graphics.
Now all three run fine.