Just after upgrading to Swedish Spring - now Marketplace won't recognise phone

[Guest CrystalLettuce]

It won't recognise the phone as being associated with my google account on PC, so I can't download from the marketplace there. This is very frustrating. Is there any way to reset it?

[Guest Phoenix Silver]

backup your applications with titanium backup

make a factory reset (in menu settings)

enter your google account again

restore your applications