Try this method from the following article:
http://support.microsoft.com/default.aspx?scid=kb;en-us;320553
I've used this method trying to restore missing CD drives in the past.
Good Luck,
John H. Wright, MCP
To resolve this behavior, use the following methods in the order that they
are presented in.
Method 1: Remove the registry entry
WARNING: If you use Registry Editor incorrectly, you may cause serious
problems that may require you to reinstall your operating system. Microsoft
cannot guarantee that you can solve problems that result from using Registry
Editor incorrectly. Use Registry Editor at your own risk.
1.. Click Start, and then click Run.
2.. In the Open box, type regedit, and then click OK.
3.. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE/System/CurrentControlSet/Control/Class/{4d36e965-e325-11c
e-bfc1-08002be10318}
4.. On the File menu, click Export.
5.. In the File name box, type savedkey, and then click Save.
6.. Click the REG_MULTI_SZ data type UpperFilters, and then click Delete
on the Edit menu. When you are prompted to confirm the deletion, click Yes.
Note If this data type is missing, go to Method 2.
7.. Click the REG_MULTI_SZ data type LowerFilters, and then click Delete
on the Edit menu. When you are prompted to confirm the deletion, click Yes.
8.. Quit Registry Editor, and then restart the computer.
Method 2: Replace the existing driver
1.. Click Start, and then click Control Panel.
2.. If Control Panel is in Category view, click Performance and
Maintenance, and then click System.
If Control Panel is in Classic view, double-click System.
3.. On the Hardware tab, click Device Manager.
4.. Click the drive with the question mark next to it.
5.. On the Action menu, click Uninstall. When you are prompted to confirm
the removal, click OK.
6.. Repeat steps 4 through 5 for any other drives with question marks.
7.. On the Action menu, click Scan for hardware changes.