Hi, the answer is to save all of the information on the card to a pc. Then while the card is in the slot and still connected to the pc, format it. This will then convert it back to an 8gb card once again. However if you still need it to work in your phone, the phone will format it once again to the 2gb size. Therefore the best advice is to buy a new 2gb card solely for the phone use. Do not buy a cheap card, as they are usually rubbish or cards that have been rejected by other suppliers, buy a decent quality card. They generally also last a lot longer and are much more reliable.
Regards.
John Bates
December 2008