DVD-ROM and CD-RW not accessible

Here is the deal if anybody can help me, I bought a DVD
burner and installed in to the computer and it never
worked. So I took it out and put the orginal CD-RW back
in the computer now it gives me this message for both of
my drives the DVD-ROM and CD-RW:

MESSAGE: is not accessible, Incorrect function.

Can anybody please help me because I can't burn any cd's
or read any cd's and I can't play and DVD's either.

What can I do to fix it????
Thanks Baddrums