Help! Need help with my 2TB hard drive

It’s my first post here on the forums so hopefully I’m doing this right :P 

Anyways, here’s my problem. 

About a year ago I got a WD My Passport external hard drive and put a lot of files from my desktop PC on it so I could then use it with my laptop as provided by my school ( both of these run windows 7). It worked fine on both computers until last week. I recently got a windows 8 tablet win 8.1 loaded onto it and it has USB support. So me wanting to watch a movie from my hard drive plug it in and get the “you don’t have permission to access this folder; access denied” etc. So then after this, I tried a lot of different things that I read on this forum and windows 8 forums to the point where i got fed up with trying. After all this when I plugged it into my windows 7 laptop I got all of the same messages and couldn’t even get the security tab in the properties menu, The weird part about all of this is that everything works perfectly fine on my desktop still. 

So what should i do? Save all my files and format it? I’m no computer expert so I can’t assume too much with a soultion explained. 

Thanks :) 

Hi and welcome Djmonize13, see if the following link helps. Try to follow these steps from your laptop.