I backracked and checked my browser history and hidden Microsoft Updates that I could not perform as well as the software I was able to install yesterday and the problems were 1) unable to install updates to the Security Update for Visual C++ 2008 Service pack 1 Redistributable, 2) unable to install updates to the Security Update for Visual C++ 2005 Service pack 1 Redistributable, 3) unable to install NitroPDF, pdf editor, 4) was unable to update AVG antivirus, 5) was unable to update the Windows Installer to version 4.5.
I tried the msconfig way, uninstalling and reinstalling the Windows Installer but couldn't uninstall it with the common error below, and as I was going to give up for another wekk or two I came across this fix on this site at: Windows Installer - Simple Fix that worked for me.
In tracing through my browser history one error was
and another one I was looking up was the common
"The Windows Installer Service could not be accessed. This can occur if running
Windows in safe mode, or if the Windows Installer is not correctly installed. Contact your support personnel for assistance."
I was so excited after searching for weeks trying to find a fix for these Windows Installer problems that I threw away my notes and just kept the fix stored in a txt file. I have no idea what the fix meant, was desparate to try anything and even contemplated a reinstall. Glad I didn't give up.