You have to do a factory reset unfortunately.

 

Yes I know it's absurd,apparently Google are working on a fix but who knows when that will be.I'm still holding out for the fix though,don't even want to think about re-organising my whole phone again.

 

I get the same problem, should I wait for the fix or spend a whole day resetting my phone up?!!

Has anyone solved the Google Talk problem yet. My market is stalled

 

Change back to googlemail or factory reset are the only options

 

had the same problem and thought it was ruining the experience of android on my new htc desire.

i bit the bullet and did a factory reset, turned out it was pretty straight forward and everything was back and synched within 10 mins, minus the apps of course and the homescreen customizations.

i go into a bit more detail on this thread

http://androidforums.com/htc-desire/93680-googlemail-warning-uk-users.html

 

I am using the HTC desire from the last one month and found only the solution to reset to factory settings. If you go to settings and then accounts and sync you will find the google talk settings there. if you try to change it you will get the message to reset it on factory settings no other solution.

Ahmed