All tool windows disappeared and won't come back

[Brian]

(11-27-2019, 08:09 AM)Blighty Wrote: Go to Edit > Preferences > Tool Options
Click on "Reset Saved Tool Options to Default Values"
Uncheck "Save tool options on exit"

Unfortunately that didn't fix it.

I'm wondering if my OS is corrupt.  I've always used GIMP, but when I switched to 2.10.12, it ran fine once, but then the next time, gave an error:
"The program cant start because libgexiv2-2.dll is missing from your computer"
and wouldn't run anymore. I switched to the portable version, which loaded and worked fine a few times, until the above problem.
FYI, this is 64 bit.