This instruction or tutorial is not from me. I got it in another site. This is very helpful when I cannot transfer anything to or from my external hard drive. It always says 'write protected'.
"During a bit of housecleaning today, I uncovered an old USB hard drive I hadn't used in a couple years. I decided to plug it in, check the contents, and see if it contained anything I still needed.
As it turned out, the drive was filled with a bunch of old, unwanted files. Great, I thought, I'll just delete them and put the drive back into use for other things.
Just one problem: when I tried to erase the files, Windows popped up an error message about the drive being write-protected. Uh, okay. Not sure why that would be, but whatever. Guess I'll just go ahead and format the drive. That'll clear everything out.
Whoops! Same error. Oh, Windows, you baffling, unpredictable, endlessly annoying operating system, you. (FYI, I'm running Windows 7 64-bit. The drive was most likely formatted using a 32-bit version of Windows XP. Maybe that had something to do with it.)
I spent some time investigating varies fixes for this problem, which can affect any kind of drive, and landed on the following:
1. Open a Command prompt by clicking Start, typing command, and clicking Command Prompt.
2. Type diskpart and press Enter.
3. Type list volume and press Enter.
4. Type select volume #, where # is the number of the drive that's giving you the "write-protected" error. In my case, I ended up typing select volume 3.
5. Type attributes disk clear readonly and press Enter.
6. Type exit and press Enter.
That's it! Now you should have full write access to the problem drive. This worked for me; let me know if you have different results."