my memory card - help

[sameh_nab]

if you please i have an o2 atom exec ppc

i was working with wm6 but today i return to the original windows - wm5 - from the official site of o2

but i found that my 1 giga transcend memory card became 460 mega only >>

i tried to return to the previous version of windows - and tried to format the memory by pocket mechanic but invain

please any one know how to restore the full space of the card ??