MS Office Professional 2013 wont let me activate stating that it has already been activated a maximum number of times. I had no idea there was a limit on this. The key has only been used on one machine but I've rebuilt it enough times that I must have hit my limit. Is there a way to fix this or is my key dead?
How many times did you reinstall MSO?
In future, just so you know, make reinstalling Windows the act of last resort rather than first. Ask for help rather than jumping on to reinstalling Windows because chances are you're wasting your time with the reinstall. Also, if anyone suggests reinstalling Windows as the first or second suggestion for solving your problem, ignore them.
I agree with mxnerd: MS will probably reactivate it for you if you ring them.