If you had set set the NoDriveTypeAutoRun Value Name by using the registry, adding the computer to an Active Directory domain causes its' data value to be reset to the default:
|Windows Server 2003||0x95|
This behavior is symptomatic of NOT having the Turn off Autoplay policy, named Disable Autoplay in Windows 2000, Disabled:
1. Start / Run / gpedit.msc / OK.
2. Navigate through User Configuration / Administrative Templates / System.
3. Double-click the Turn off Autoplay policy.
4. Set it to Disabled.
5. Press Apply and OK.