What is the "msiexec.exe" process on windows 8? Is the "msiexec.exe" process a virus? Can I terminate the "msiexec.exe" process?

"msiexec.exe" process represents "Windowsr installer" program.

"msiexec.exe" process is normally running under the parent process "Boot" as shown in the process tree below:

Boot
   msiexec

On the Processes tab of "Task Manager", "msiexec.exe" process may be listed as:

Image Name                 Memory   Description
--------------------   ----------   -----------
msiexec.exe               9,328 K   Windowsr installer

Additional information about "msiexec.exe" process:

Command line:
   C:\Windows\system32\msiexec.exe /V

Programe file information:
   Name: msiexec.exe
   Location: C:\Windows\system32\msiexec.exe
   Description: Windowsr installer
   Version: 5.0.9200.16384 (win8_rtm.120725-1247)
   Size: 124416 bytes
   Last modified: 7/25/2012 11:08:34 PM
   Company Name: Microsoft Corporation
   
Some data files used:
C:\Windows\System32
C:\Windows\System32\en-US\msiexec.exe.mui
C:\ProgramData\Microsoft\Windows\AppRepository\edb.log
C:\ProgramData\Microsoft\Windows\AppRepository\PackageRepository.edb

Some registry keys used:
HKLM\SYSTEM\ControlSet001\Control\SESSION MANAGER
HKLM\SYSTEM\ControlSet001\Control\Nls\Sorting\Versions
HKLM\SYSTEM\ControlSet001\Control\Nls\Sorting\Ids
HKLM\SOFTWARE\MICROSOFT\WindowsRuntime\CLSID
HKCR\ActivatableClasses\CLSID

Some DLL libraries used:
C:\Windows\SYSTEM32\ntdll.dll
C:\Windows\system32\KERNEL32.DLL
C:\Windows\system32\KERNELBASE.dll
C:\Windows\system32\apphelp.dll
C:\Windows\AppPatch\AppPatch64\AcLayers.DLL
C:\Windows\system32\msvcrt.dll
C:\Windows\system32\USER32.dll
C:\Windows\system32\SHLWAPI.dll
C:\Windows\system32\sfc.dll
C:\Windows\system32\WINSPOOL.DRV

"msiexec.exe" process is not a virus. You should not terminate "msiexec.exe" process.

⇒ "alg.exe" Process on Windows 8

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⇑ System Service Processes on Windows 8

⇑⇑ Windows 8 Processes Tutorials