To be honest....... if you pay less than a tenth of the cost....... do you REALLY expect it to be legal??? and not blacklisted at some point?? If I remember rightly are MSDN keys only supposed to work 10 times? I know they will activate more than 10 times but it must get flagged somewhere ???
Some MSDN Keys are 10 times and others are 100 times.... either way..... the seller should have told you - who many times it could be used. Then you should have made a FULL BACKUP of the original install&activation. then you could restore and it would be activated.... or you could have made a BACKUP of your Token and pkeyconfig. then you could restore it... you can also simply rearm and get legal, then use ODIN or Orbit30 ULoader 8.0 to activate.... both mentioned programs work 100% for me on many different manufacture systems - and different editions from HomePremium - Professional - Ultimate.
Each MSDN retail Key has 10 Online activations and 20-25 Phone activations, Only a MAK key has activations greater than 100.
None of the keys you buy will be trustworthy bottom line is people are not allowed to sell keys so any one offering them for sale can't be trusted.