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

Retrieves the serial number of any portable media player connected to your computer. If this service is stopped, protected content might not be down loaded to the device.

The Portable Media Serial Number Service does not exist in:

Default Settings

Startup type: Manual
Display name:Portable Media Serial Number Service
Service name:WmdmPmSN
Service type:share
Error control:normal
Path:%SystemRoot%\System32\svchost.exe -k netsvcs
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WmdmPmSN

Default Behavior

Portable Media Serial Number Service is a Win32 service. In Windows XP it won't start until the current user starts it. When the Portable Media Serial Number Service is started, it 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 Service 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 WmdmPmSN service has failed to start.

Restore Default Startup Configuration of Portable Media Serial Number Service

1. Run the Command Prompt.

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

sc config WmdmPmSN start= demand

3. Close the command window and restart the computer.

The WmdmPmSN service is using the mspmsnsv.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.