A question containing COM1 as title will trigger this error
https://stackoverflow.com/questions/1677444/COM1
Server Error in '/' Application. The resource cannot be found. Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Please review the following URL and make sure that it is spelled correctly.
Requested URL: /questions/1677444/COM1
web.config
tags too (don't know if it was fixed and I'm way too lazy to look it up, but not lazy enough to stop typing in the comment box provided by our benefactor or overlord, wich one you prefer. I'm sorry I wasted your time when you could be anywhere else doing something productive. Go now. Put that giant S down. Please don't hurt me. Stop hitting me. Please! Waaah! ... pluralization errors censored)