WD Hdd problem

Can anyone help me about my HDD, it won’t read/open on any windows format comp. But on MAC comp. No problem on it running.
In windows the disk drive appears but cannot open, any ideas what happe ed to my HDD? Thank you in advance…
Answer #1
Did it used to work in windows?
Did you format or change the format under Mac?
http://www.wikihow.com/Format-a-Hard-Drive-on-Mac-to-Work-on-Mac-and-PC
Answer #2
Yes it was working on windows before. Now it is still reasding the drive but cannot be opened, in mac it has no problems at all opening viewing my files.