My Western Digital Passport has suddenly decided it does not like me. I connected the WD using the USB cable and I get a message that the drive needs to be formatted. The WD was working fine when I last used it. I do not want to format the drive and lose all the data.
Sorry to hear about the problem. I hope by now you have resolved the problem, but in case you haven't, here is some info on the problem.
External drives often ask to be formatted when they are not ejected correctly. Windows writes a bit of info on the drive indicating that the drive was indeed ejected correctly and none of the cached data was lost. if you disconnect it without the safe eject option, Windows cannot find that piece of data and assumes that the drive has lost some data (not always) and thus requires formatting.
Could you post a screenshot of the way the drive is seen in device manager and disk management? As a last resort you can try the drive on a different computer or simply use Linux to get your data back and then format it.