Let's be clear on one thing: Formatting a drive is a very effective way to fix it; this solution works most of time, and it doesn't matter whether the drive is a hard drive, memory card, USB or thumb drive. But you won't always be so lucky. Sometimes, formatting a drive just won't cut it, and you'll need to resort to other options. A simple example of when formatting fails to achieve the desired effect is when you get the 'Windows was unable to complete the format' error.
Here's an alternate way to fix a Raw drive: You convert it into NTFS, FAT32, or any other recognized file system. When you try Windows quick format or maybe 'Disk management' and neither of them are able to format the drive, give 'disk part command line' a shot and see what happens. Do this:
1Click on 'Start', then in the menu that appears, just type 'cmd' and press 'Enter'.
2 Right-click on 'cmd' and you'll see a pop-up. Click on 'Run as Administrator'
3Type 'Disk part', then press 'Enter' once more.
4Now, type this command: 'convert X: /fs:ntfs.' Once you do that, press 'enter' again. In case you're wondering, you'll replace 'X' with the letter of your Raw drive. And be aware that you can replace NTFS with the other file systems- fat32, exfat, etc.).
If this happens, it just means the drive must have suffered extensive hardware damage. If that's the case, then it's time to pull out your trump card, which is the low-level format. Doing that will erase everything in your raw drive, and you won't be able to recover any data that was in there. So always this have this at the back of your mind: Recover data from your Raw drive BEFORE you format or else you can bid your files farewell.