Are you sure it is a sandisk memory stick pro duo? i.e. this one.. http://www.sandisk.com/Products/Item(1057)-SDMSPD-1024-SanDisk_Mobile_Memory_Stick_PRO_Duo_1GB.aspx
i own a sony ericcsson k800i and recently i bought a sandisk 1gb memory card for it. it doesnt fit as it is slightly different to the sony ones which are alot more expensive. does anybody know if theres is a memory card out there that fits sony ericcsson phones and doesnt cost a fortune???