I checked the forum and I didn't see anyone having this small issue, but I was wondering if anyone knew anything about it?
The message "ERROR : Error Code Does Not Indicate An Error" message keeps popping up all of the time. There appears to be no issue with this happening, but it is a real annoyance.
Has this happened to anyone else and does anyone know why this is happening?
Thanks very much for any info.

Thank you very much Ralackk, you solution fixed my problem.

Doesn't turning off midi remove the sound or music from the game though or are you able to select a different output?

Yes, it sounds like it turns off the background music, but everything else sounds fine. I miss the background music, but I hated even more to have to keep clicking away that error message that would pop up constantly.

Do you know if that error only popped up in certain places within the game when certain music was playing or did it appear to just generally be all the time?

this is a standard error with xp & overseer. GOG disabled the midi for a reason, later in the game it will crash without the midi being muted. (at gideons gallery)

The error message would pop up all of the time.

Turning off MIDI will stop the "error" but will disable background music. A proper fix for Windows 7 is here and worked for me:
[url=https://pcgamingwiki.com/wiki/Tex_Murphy:_Overseer#cite_note-Waltc-1]https://pcgamingwiki.com/wiki/Tex_Murphy:_Overseer#cite_note-Waltc-1[/url]

If you have any problems getting the various downloads referred to, I have local copies available.

one bit of software solved all of these problems for me (and makes a lot of old dos games sound amazing)

MUNT MT-32

lots of tuts online...

try it once, never go back... ;D