PC NOT DETECTING USB DRIVE/PEN DRIVE

This problem occurs when no device is connected to a USB port. That makes the USB driver set the Open Host Controller Interface (OHCI) controller to a suspended state. When the OHCI controller is in a suspended state, it cannot always detect when you add a new USB device to your computer.

Prerequisites

To fix this problem on a Windows XP-based computer, you must be running Service Pack 1 (SP1) or later. To determine if you have Windows XP SP1 or later, click Start, click Run, type winver, and then click OK. If SP1 or later is not listed in the About Windows dialog box, then install the latest service pack before you try to fix this problem.

Steps to fix this problem

Create a new registry value that prevents an OHCI controller from entering a suspended state.

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

How to back up and restore the registry in Windows

To create a new registry entry that will disable the Selective Suspend feature of the USB hub driver, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\USB
3. On the Edit menu, point to New, and then click DWORD.
4. Type DisableSelectiveSuspend, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type 1, and then click OK.

Note This setting affects all USB host controller drivers in the system.

If the value of the DisableSelectiveSuspend registry entry is set to 1, the Selective Suspend feature is disabled. Additionally, the Allow the computer to turn off this device to save power check box does not appear on the Power Management tab for the USB Root Hub.