Any of the WCF services fail to start either during the installation or while patching.  You may receive and error similar to "Error 1920.Service [service name] failed to start. Verify that you have sufficient privileges to start system services."

Cause / Resolution

This error can have several different causes.  Below are known causes and resolutions.

Account Doesn't Have Sufficient Privileges

Click Start >> Run >> type "secpol.msc" >> hit Enter
  1. Open Local Policies >> User Rights Assignment
  2. Double-click "Log on as a service" and click Properties
  3. Click "Add User or Group... " and add the service account
  4. Double-click "Deny log on as a service" and click Properties
  5. Make sure the service account is not listed
  6. Close down the Security Policy Window and try again

IE Blocking Certificate Verification

Open Internet Explorer and select "Tools" >> "Internet Options"
  1. Click the "Advanced" tab
  2. Scroll down in the "Settings" section to the "Security" heading
  3. Uncheck the item "Check for publisher's certificate revocation" (This may also require unchecking "Check for server certificate revocation" and "Check for signatures on downloaded programs" too.)
  4. Close Internet Explorer and try again

To configure revocation settings on a local computer through group policy:
  1. Click Start, type gpedit.msc in the Search programs and files box, and then press ENTER.
  2. In the console tree under Local Computer Policy\Computer Configuration\Windows Settings\Security Settings, click Public Key Policies.
  3. Double-click Certificate Path Validation Settings, and then click the Revocation tab.
  4. Select the Define these policy settings check box, select the policy settings that you want to apply, and then click OK to apply the new settings.

Missing Pre-Requisites

Download and install Microsoft Visual C++ 2010 SP1 Redistributable Package (x64).

Required Port Blocked

Run the command "netstat -ano" in the command prompt and look for the service's port being used by another service/process.
PStore Keys Writing Incorrect Values to Service Configs
Run the following command as administrator to remove PStore keys:
REG DELETE "HKLM\Software\AccessData\PStore"
Server names are wrong
When prompted for machine names for the servers, type the names to ensure strange hidden characters aren't copied and pasted.  This may also require first deleting the PStore keys as documented above to make sure it's not reading bad values from the registry.

Login as the Service Account

Be sure to login as the Service Account while installing services.  

Windows Services Dependencies

AD Summation Pro and eDiscovery depend on certain Windows Services in order to install and function properly.  The list of dependency services can be found here.
(Note: Although the Windows Event Log service may be running, it possible that its not logging any data.  The AccessData RTT Business Services (and possibly others) must be able to log entries into the Windows Event Viewer for it to install and run correctly.)