regsvr32.exe

In computing, regsvr32 (Microsoft Register Server) is a command-line utility in Microsoft Windows operating systems for registering and unregistering DLLs and ActiveX controls in the Windows Registry.

To be used with regsvr32, a DLL must export the functions DllRegisterServer and DllUnregisterServer.

regsvr32 shmedia.dll for registering a file

regsvr32 /u shmedia.dll for unregistering a file

If another copy of shmedia.dll exists in the system search path, regsvr32 may choose that copy instead of the one in the current directory. This problem can usually be solved by specifying a full path (e.g., c:\windows\system32\shmedia.dll) or using the following syntax:

regsvr32 .\shmedia.dll