Portable Media Serial Number (WmdmPmSp) Service Defaults in Windows XP

Retrieves the serial number of any portable music player connected to your computer.

The Portable Media Serial Number service does not exist in:

Default Settings

Startup type: Automatic
Display name:Portable Media Serial Number
Service name:WmdmPmSp
Service type:share
Error control:normal
Object:LocalSystem
Path:%SystemRoot%\System32\svchost.exe -k netsvcs
File:%SystemRoot%\System32\mspmspsv.dll
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WmdmPmSp

Default Behavior

Portable Media Serial Number is a Win32 service. In Windows XP it is starting automatically along with the operating system. Then the Portable Media Serial Number service is running as LocalSystem in a shared process of svchost.exe. Other services and drivers are allowed to run in the same process. If the Portable Media Serial Number fails to start, the technical information about the error is added to the Event Log. Windows XP startup should proceed, but a message box should be displayed informing the user that the WmdmPmSp service has failed to start.

Restore Default Startup Configuration of Portable Media Serial Number

1. Run the Command Prompt.

2. Copy the commands below, paste them into the command window and press ENTER:

sc config WmdmPmSp start= auto
sc start WmdmPmSp

3. Close the command window and restart the computer.

The WmdmPmSp service is using the mspmspsv.dll file that is located in the C:\Windows\System32 directory. If the file is removed or corrupted, read this article to restore its original version from Windows XP installation media.