Hi, i also have an HTC TyTN 2 that came with Windows mobile 6 on it, HTC were (and still are) offering customers a FREE update to Win Mob 6.1 Pro all you need to do is input your serial no on the support link og HTC's website, if you reguarly sync your pda with your pc, and your map software is on your micro sd card as mine is, its no grief at all, follow the read me instructions carefully cos if you mess up you could be left with no OS, but yes it wipes all your info off the device and puts a new ROM image on, MAKE SURE YOUR MICRO SD CARD IS REMOVED DURING THE PROCESS, and then once updated re-sync it with your PC and all your information will be restored to the device, i had to load tom tom nav 6 from the cd-rom again but thats no grief, and when i re-inserted my micro sd card with tomtom western europe map software on it and booted up the TomTom program, it works fine, theres no changing product codes or anything like that to worry about.