This weekend, I was asked to look at a system that wouldn’t allow the owner to use a USB External Harddrive (Maxtor Personal Storage 3200, 160GB). It was correctly seen by the machine and available in device manager, and the disk management utilities. However, it wasn’t assigned a drive letter by default, and attempts to assign it one failed. Windows would indicate that it had a drive letter but it never showed up in Explorer and reboot or refresh the disk management list and the drive-letter would be removed.
In the Event Viewer, I found the following error:
Event Type: Warning
Event Source: PlugPlayManager
Event Category: None
Event ID: 270
Time: 7:54:53 AM
Plug and Play user-interface dialogs have been suppressed in Factory Mode.
After searching the internet, I found a reference to this message, and a “FactoryPreInstallInProgress” registry key that appears to have fixed the problem:
Under the Startup key, deleted the
Deleted the entire
Reboot, and it detected the hardware and displayed the balloon help indicating that it was successfully connected to the system. The USB hard drive was given a drive letter and everything worked as expected.
According to Microsoft, we as consumers shouldn’t see a system in this state. However, this particular user had a replacement e-Machine sent to him when his original failed, under warranty. I am guessing that some e-Machine technician didn’t complete some final step (removing this key/etc) before boxing and shipping the system out.