if you truly have a password with upper and lower case letters and numbers, the chance of a batch password cracking program successfully coming up with your number is virtually nil.
Someone either physically accessed your machine or virtually did so.
Please when you scan, you must do it in safe mode with restore turned off.
A great program is ewido, works wonderfully for me, also trend online is great also.
personally if none of them find anything i would completely format your machine, possibly with a formatter using 1's and 0's. Because some rootkits are virtually impossible to find by any means.
We had an attack on one of our websites and it completely destroyed it, it took me 9 months to get all the content back on it, and we make millions and are one of the largest companies in the world for what we do.
I'll ask tomorrow and see what program we used to scan our servers, but we did pay a consultancy firm i think $150,000 to do this.... so you see what you are up against.
just my opinion.