Follow the Steps below :
1) Goto Run (Start»Run OR Win Key + R)
2) Type cmd and Ok
3) Change the drive location to the drive which is not opening (Drive letter followed by colon e.g. E:)
4) Type following command confirm if autorun.inf file is present there
5) Type: attrib -S -H -R autorun.inf
6) Type: del autorun.inf
7) Now simply go and rename the original drive label in My Computer.
If this work for the first drive then try same steps for your second drive.
It should work.