Peewee, firstly, calm down. Secondly what exactly does happen when you try to read the data on the stick? Can you see files listed using Windows Explorer? (Are you using Windows? Which version?). What error messages do you see? Check that there is no dust in the stick or in the slot you use.
If not, try the stick on another computer. If you can then see data files listed, copy the files to that computer, and from there onto another stick. Don't do ANYTHING which involves writing to the original data stick. If it has a write-protection notch, activate it. (It might have a small sliding switch to let your computer know not to write to it.)
I hope you have at least one backup, with another being looked after by someone else, in case of flood or fire? And that your backup data has been tested. I'm not being hard or facetious, just giving you the benefit of my experience.
Backed up data is no good if you aren't sure that it can be used. Ideally data should be backed up onto a series of three or more sources, so that you can always fall back to an earlier version.
Now that you are calm, provide me and others more details. What has happened since the data was OK? Do you have data on the PC's hard disk? More later when I've seen your answers.
Martin
