HRESULT: 0x800f0818 Unable to add/modify Roles or Features through Server Manager or Powershell after installing updates

After installing numerous Windows Updates, usually when bringing a newly installed server up to date on patches, you may recieve the following error in server manager:

Error: Unexpected error refreshing Server Manager: Exception from HRESULT:0x800F0818d

This issue occurs when corrupt .mum or .cat files are present after the extraction and installation process of windows updates.

To reolve this we need to complete a few steps

1. Download and run the Microsoft Update Readiness Tool from http://support.microsoft.com/kb/947821 once it has run check the log in C:\Windows\Servicing\Packages\CheckSUR.log or %SYSTEMROOT%\Logs\CBS\CheckSUR.log

2. You should see errors resembling:
CBS MUM Corrupt 0×00000000 servicing\Packages\Package_for_KB978601~31bf3856ad364e35~amd64~~6.0.1.0.mum Expected file name Package_for_KB978601_server~31bf3856ad364e35~amd64~~6.0.1.0.mum does not match the actual file name

and further down

Unavailable repair files:
servicing\packages\Package_for_KB978601~31bf3856ad364e35~amd64~~6.0.1.0.mum

3. There may be more than one problematic update so make a note of all of them, you will then need to download these KB’s and unpack them using the following commands:

Expand -F:* UpdateKB978601.msu C:\Directory

This then shows a cat file which also needs to be unpacked:

Expand -F:* UpdateKB978601.CAB C:\Directory\CAB

 you can use any software to extract CAB files like Izarc.

4. You will need to grab the two files, one extension .mum and one extension .cat, then rename them making sure they are exactly as was displayed in the CheckSUR.log file. You will then need to copy them into the C:\Windows\Servicing\Packages directory overwriting the existing ones.

These steps should resolve the issues and you should be able to add/remove Roles and Features again