Re: not able to open c and d driver
Sorry, but I don't understand your question ...
"C" and "D" are drive letters that MS Windows assigns to partitions (even though it wrongly calls them "drives") -- and these have nothing at all to do with Ubuntu, since Linux does not use drive letters.
If you're trying to mount the "C" or "D" partition (and that's failing), or if you are mounting those but can't write to them -- you need to tell us this.
Ubuntu 14.04, Mint 17; MS Win 8.1.
Will not respond to PM requests for support -- use the forums.