I recently rebooted to find mIRC was missing it's settings (like I'd just installed it) so I want to %appdata%\mIRC and had a look and found these two files but no mirc.ini:

Code:
12,117 mirc396.tm_
12,108 mirc397.tm_


I took a look inside them to find they were the mirc.ini so I just copied the most recently dated one to mirc.ini (copy mirc396.tm_ mirc.ini) and everything was fine again.

Don't know if it's a bug or not but thought I'd say in case.