04 Oct 2009 at 14:08 - 4
If you bought the retail package of GW, there would usually be a "buddy" key which you can give to a friend as a trial key. People have been known to use this key instead of the proper "real" key. Look through the materials that came with the game and check if there is another key.
If this is the case, just add the proper key to your current (trial) account and everything should be good to go from where you left off.
Of course, there's always the possibility that you bought a used game and got ripped. :P