To format the internal memory card. 1. Open the Control Panel and click the Memory Icon. 2. UN-check the "extended memory box" (this is what is using the internal card) 3. Test by plugging in the USB if it doesn't work then do steps 4 otherwise, skip it and go to 5 4. Shut down the n800 and switch the internal and external card (don't worry it won't hurt anything.) 5. Turn the n800 back on when booted plug it into your Windows system (PC's where built by IBM.) and format the disk. Make sure you do it fat32 not fat 16 as fat32 is the one used on these especially if you have a SDHC (4G or larger) card. 6. Turn the n800 off (if you did step 4) and switch the cards back. 7. Open the Control Panel again and this time check the box for extended memory. Done.