WZ, groan... IF in fact the card has been reformatted on some Windows PC to FAT32, then it's now got a 4Gb limit.
Macs will merrily format FAT32 to the 128Gb limit. (I'm not sure what the world is going to do with 256Gb USB sticks, by the way!)
If you know someone with a Mac, then you can get them to reformat it, AND the Windows machines can READ and SAVE files onto it afterwards.
Your next option is to get Linux LIVE BOOT CD and let a PC boot up into a "Live Trial Linux", and then let this Live Trial Linux "PC" do the FAT32 formatting. (This does NOT install Linux - you're only 'testing it', running your PC's CPU, memory, video and USB functions from that booting CD.)
Ubuntu offers you a way to download its "ISO" installation disk that your Windows PC can burn onto a (DVD or CD - I forget which). Then, I can boot up with that CD/DVD and select "Run Live Linux" from there.
There's probably a better way around all of this, but I've got a spare Mac that has saved my cards a time or two.
(By the way, there is an earlier comment about the possibility of a "fake" chip. Sadly, that IS a possibility as well. I'd take it to some shop - even like an OfficeDepot or OfficeMax, Staples - that also have Macs and see if they can read it - and maybe format it! Wheeeee)