WD My Passport 1TB HD "Invalid password" error PLEASE HELP!

It’s been a year since I’ve started using my 1TB harddrive. Just recently, the autounlock feature (which I’ve switched on ever since I used it on my laptop) stops working and asks me to unlock the drive. I enter the correct password and it takes around 20 secs to process then shows the “invalid password” message. I know the password is right because I have another 500GB harddrive which has the same setting. For some reason only the 1TB HD is showing this error while the other unlocks just fine. Is there any way to fix this problem without erasing the data? 

PS: I tried plugging it into another PC and it says that the driver software cannot be recognized/installed.

PPS: My laptop is running on Windows8.

Hello and welcome to the WD community.

I recommend contacting support for further assistance on this matter this is not normal behavior for this unit: