IIS Admin Service failed to start with ‘Class not registered’ error

This post has been republished via RSS; it originally appeared at: New blog articles in Microsoft Tech Community.

I came across a scenario where IIS admin was failing to start with error

--Checked procmon which is a must go tool for  such issues

--tracing it , I could see below

1:46:11.7430366 PM      inetinfo.exe       9184       7516       RegOpenKey      HKCR\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}                NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:46:11.7431643 PM      inetinfo.exe       9184       7516       RegOpenKey      HKCR\WOW6432Node\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}            NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:46:11.7437105 PM      inetinfo.exe       9184       7516       RegOpenKey      HKCR\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}                NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:46:11.7438050 PM      inetinfo.exe       9184       7516       RegOpenKey      HKCR\WOW6432Node\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}            NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:53:01.7480590 PM      inetinfo.exe       9440       9812       RegOpenKey      HKCR\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}                NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:53:01.7481572 PM      inetinfo.exe       9440       9812       RegOpenKey      HKCR\WOW6432Node\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}            NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:53:01.7485668 PM      inetinfo.exe       9440       9812       RegOpenKey      HKCR\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}                NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

1:53:01.7486327 PM      inetinfo.exe       9440       9812       RegOpenKey      HKCR\WOW6432Node\CLSID\{BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}            NAME NOT FOUND         Desired Access: Read      NT AUTHORITY\SYSTEM 0

this key HKEY_CLASSES_ROOT\CLSID\{BA4E57F0-FAB6-11cf-9D1A-00AA00A70D51}\InprocServer32 has the value %windir%\system32\inetsrv\metadata.dll  which was missing

--I did  a test on my machine by deleting BA4E57F0-FAB6-11CF-9D1A-00AA00A70D51}      from HKCR node

--got the exact error

Such issues can come up after OS upgrade, while doing a registry restore/backup