Hi Sue, Before you reformat, it would be best to discover the cause of the problem. The most likely cause is that the flash drive is faulty. First, I would try the flash drive in another pc. That will at least prove the condition of the flash drive, either way. If a another pc cannot read it, then either try formatting it fat32 or return it to where you bought it. If the flash drive proves to be good in another pc, here are a few thing to check... 1. Scan for a virus. There are a few around that will cause this problem. 2. Do you know that you have usb2? If you have usb1.1, it may work with some flash drives and not with others. 3. Check the usb drivers are ok. Try reinstalling your usb drivers. 4. The extended fat driver. The exfat format was introduced in Vista. Microsoft supplied an exfat driver for XP. I think it came in sp2 and sp3. There were a few complaints, that after sp3, the exfat driver in XP sometimes caused problems when reading/ writing fat32 drives. The symptoms were the same as yours. There are many other possibilities. Les Hardy Les, and others, Microsoft Windows XPHome edition, compaq lap top, version 2002. Flash drive is Dane-Elec 4 GB. Is that enough information ? So is my flash drive useless ? Should I re-formatt it ? Should I get another brand flash drive. This is the second Dane I have and no problem with the first, smaller size. I can get the information again, it is my genealogy. Tthis was to be a back up file. Maybe I should store everything on "Drop Box" Thanks to all, Sue *On Fri 02/10/12 10:48 AM , Les Hardy [email protected] sent: * Hi Sue, I would guess the problem was not caused by you. Not using safe removal, should at the worst just corrupt a file or two. I can think of a few possible causes, but first can you tell me what hardware, and operating system you have, and what brand is the flash drive? Les Hardy