I spent a large amount of time over the past few days trying to get AVG Anti-Virus Business Edition 2012 installed on a server running Microsoft Windows Small Business Server 2008 64-bit edition.
Server had an older version of AVG 8 or 9 Network edition that was at end of life and I couldn't get a new license for it so the customer requested 2012 business edition. Uninstalled the old version and upon trying to install 2012 I recieved.
AVG Software Installer
Error Code: 0xc0070643
Error Message: General internal error
Additional messages: MSI Engine: Failed to install the product.
Context: AVG product installation
I ran the AVG removal tool, AVG reset access utility, ran CCleaner, manually removed every folder from program files and program data, removed every reference to AVG in the registry, reinstalled Microsoft Visual C++ 2005 \ 2008 and all updates, reinstalled .NET framework 3.5 and 4, ran the .NET Framework Setup Verification Tool, Download Update for Root Certificates, Windows updates complete up to 11/2/12 but none of that helped
I was in touch with a very good tech the entire time and we were both stumped, I sent off my failed setup logs and a few days later I received.
It appears that the issue is caused by the SharePoint plug-in installed by AVG. The AVG installation error log reports that it cannot restart the Microsoft SharePoint service because it is disabled. The MS Info also states that the SharePoint service (C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\bin\wssadmin.exe) has also been disabled.
AVG temporarily stops the SharePoint service, installs the AVG SharePoint plug-in, and then reattempts to restart the SharePoint service. If the service has been disabled, then AVG cannot start it, causing AVG to error, and thus causing the error message.
The fix for this is to either not install the AVG SharePoint plug-in during the custom installation, or enabling the SharePoint service.
During the setup once I got to Custom Options and from Server Addins I unchecked Document scanner for MS SharePoint and it finally installed
Ive found no other reference to the SharePoint service and 0xc0070643 so I hope this small amount of information saves someone else hours of frustration.