Microsoft Office 2010 corruption and inability to re-install

A client called this morning with a may-day... Microsoft Office 2010 Home and Business edition is unable to run.
As usual, tried the repair, even tried uninstall and re-install - hey, I have an adventurous client here! - but it did not resolve the problem.

To make things worse, the Ms Office is now unable to be installed with an error stating that there's error 2086. 
(I have already stopped the antivirus, run as administrator and saved the entire CD to my D drive...)

Went online, do my usual ritual of google-ing for things... 

1st link: doesn't help as i have given administrative rights to install and even tried turning off the antivirus (trend micro wfbs corporate)

2nd link: gave me more info on the nature of the problem. rooted to .net frame work installation that is required.

Decided to try doing a Windows update, and to my horror, .net framework 4.0 update failed with another error!

Windows update returned error 643, and upon searching for answers, found this link. 

Looked at both solutions, tried the Microsoft Fix-It first, duh- so easy... But it didn't resolve the problem.
Went on to the second solution to repair the .Net frame work client profile.... then restarted the machine.
After the machine restart, I proceed with the .Net framework 4.0 update again (which is successful). I do know that without this update, there is high possibility that I will not be able to install the MS Office 2010.

Aha! that solved the problem and Ms Office 2010 is successfully installed. Proceeding with Ms Office Service Packs and updates!!!