Registry Server - REGSVR32.EXE

The Regsvr32 tool is commonly run after installing new programs. It's an application supplied by Microsoft to register new programming objects. Usually it's run once for each new module installed by a new setup program. Many programs, including Windows Update, will create an entry with RegSvr32.exe followed by a new component as a way to register new files.
WinPatrol users may see this in a "RUNONCE" alert. Unless an alert for RegSvr32.exe comes unexpectantly, you should reply Yes, allowing this program to be added to your list of Startup Programs. As a RUNONCE entry, it will automatically be removed once it runs.

The parameter of Regsvr32 will be an OLE control such as a DLL, ActiveX component or other module with information that will be added to the Windows system registry. Regsrv32 is also used to "Un-Register" controls so it may also be seen when you properly uninstall a program.

Recently, it was part of a wide spread Windows tip to protect users from a security flaw in WMF image files. Users were instructed to type in "regsvr32 /u shimgvw.dll" to Unregister the flawed DLLuntil Microsoft released a security patch.
Once a system was patched, the file could be reregistered by typing "regsvr32 shimgvw.dll"

Regsvr32 Parameters       [/u] [/n] [/i[:cmdline]] dllname
      /u - Unregister server
      /i - Call DllInstall passing it an optional [cmdline]; when used with /u calls dll uninstall
      /n - do not call DllRegisterServer; this option must be used with /i

Explanation of Regsvr32 Usage and Error Messages (Q183887)

Safe

Will usually remove itself

Microsoft.com