find disk management in control pannel type in: administrative tools and than open computer management. under storage find disk management and there you will have it all listed. Now you need to assign letters D,E (or whatever) to your missing drives.
Before reading your post, I went to management and found my missing drives with exclamation points. I uninstalled the drives and rebooted but that did not work. Then I used system restore and my drive problem was solved. Thank you for your kind (and rapid) response.