I'd use SYSTEM RESTORE (a Windows 7 feature) to roll back to when it worked.
http://www.computing.net/answers/hardware/my-computer-detect-my-pendrive-as-a-cd-rom/67173.html is an interesting read too.
Bob
Hi,
Windows 7 was detecting my pen drive normally but recently it turned to detect the pen drive, external hd and 3G modem as a cd rom unit.
Because of that the disconnect safely option doesn't appear anymore despite I have normal access to the data in the devices.
I already tryied to disable the devices and enable them again but it didn't work.
I would appreciate any help.
Thank you.

Chowhound
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