Flash drive only works on mac

[jschlis]

My usb verbatim 2 gb flash was working fine in my 3 work computers and 2 home computers, all pc's. I used it in the mac and now it only works in the mac. When I plug it into any pc it shows up in "my computer". When I click on it I get the "open with" window asking me what program I would like to open this with. Put it back in the mac and it works fine. Any help would be greatly appreciated.