To find the issue you can try:
1) use your current mIRC install and
-Unload all your scripts but a single script file containing the on exit event, can you reproduce?
-If you can't, reload one script at a time until you can. If you end up reproducting after reloading one of your script, then that script would be causing it somehow.
-If you can reproduce immediately without reloading any script, then other scripts file aren't causing it.
2) if you can reproduce immediately without reloading any script from 1) then you could try to reproduce on 7.76, 7.75, etc until you can't reproduce anymore, and then it should indicate that some bugs were introduced in the mIRC version after the one you can't reproduce on.
3) If you can reproduce on 7.76 7.75 etc and you're have tested 10+ older versions, it may indicate some mirc.ini corruption (possibly other mIRC INI files).
