Error "Windows was unable to open service WdiServiceHost for writing on local "

I am getting this error Windows was unable to open service WdiServiceHost for writing on local. Anyone know a fix for the error Windows was unable to open service WdiServiceHost for writing on local computer.

It may be the service itself or a missing dependency. Normally, this service is not set to start automatically but rather manually (on demand). Run services.msc from the start/search line and scroll down to the Diagnostic Service Host. Double click it and check the settings to ensure it's set for manual. On the Recovery tab, you may want to set the first failure option to restart the service.

It's set to manual and has no dependencys also the start stop buttons are greyed out the recovery tab gives this error Windows was unable to open service WdiServiceHost for writing on local computer.

Followup I get this in eventviewer The Diagnostic Service Host service failed to start due to the following error:A privilege that the service requires to function properly does not exist in the service account configuration. You may use the Services Microsoft Management Console (MMC) snap-in (services.msc) and the Local Security Settings MMC snap-in (secpol.msc) to view the service configuration and the account configuration.

What account shows as being used on the logon tab of the service's properties. It should be Local Service - have you disabled any of the system accounts. I deleted the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WdiServiceHost\Security key and the start button is no longer gryed out but I now get this error when I click the start button.

In our case we were enforcing what accounts could do things and Windows 7 has one more account that needs to be able to have permission.....but it isn't easy to get it back in there if you ever stripped it out.