Can you see if mIRC is leaving anything in the Event Logs?

Once you have Event Viewer opened, on the treebar on the left side: Event Viewer -> Windows Logs -> Application

Scroll thought it and in the "Level" section, look for "Error", click those and look for the ones with mIRC.

You should see some stuff like this "Faulting application name: mirc.exe, version:". (like here).

Paste that info here.

Can you run this and paste the contents here:

//echo -a $os $version $beta $md5($mircexe,2) $file($mircexe).sig $alias(0) $script(0) $dll(0) $com(0) #msl (mIRC Scripting Language)