[636 rider]

this might sound like a crazy question but how do I transfer data from one card to another without loosing anything ?

[Tremortality]

Enable Mass Storage Mode and put it on the PC - then insert the new card - move from PC to BB. Or if you have a card reader you can just move it that way. Alot of older PC's do not have card readers built in.

To enable Mass Storage
options>media card>mass storage mode support = ON. Once you have done that its as simple as plugging in the device (via the USB cord) and dragging and dropping what you wish to and from the BB/PC. Treat it like you would any other flash/removable drive. Browse "my computer" and look for blackberry listed as one of the drives...

[Xopher]

Make sure to you Safely Remove the BB from your PC. If not, it may disable the SD card until you run CheckDisk on it (BB won't let you use the SD card until you do so). It's easier just to get into the habit of using Safe Removal procedures to begin with.

[ClayShooter]

You can also remove it from the BB, put it in your PC, copy to the PC, swap the cards, copy back to the card, and then put the new card in the BB.