FrameMaker 2019 won't save properly

When running FrameMaker 2019 on Win7 - 64 bit, I keep getting these error messages when working. I can make themm go away for a short time by saving to mif, and reopening and saving as fm, but the errors keep coming back a bit later. I can't figure out what is happening.

Any advise? ...

[Question moved from the Acrobat forums to Adobe FrameMaker . -Mod]