Umm, ok, that doesn't provide much information. Click Start-Run-Type
devmgmt.msc and click OK. Expand DVD\CD Drives and see if there is
anything listed. If there is a yellow icon on it, right click on the
drive and click uninstall. Now reboot. As for the external drive, was it
working before? Was any of this working before or did you just install
Windows? Have you tried Windows Update? There are too many questions
that are able to be asked because your info is too broad