A possible Fix
There is a program called Windows Installer Clean Up here...
http://download.microsoft.com/download/e/9/d/e9d80355-7ab4-45b8-80e8-983a48d5e1bd/msicuu2.exe
From all I read on the millions of posts all over the internet, the problem seems to show up when you have a previous installation of MSSQL Server and the "fix" is to erase that copy. I tried uninstalling it repeatedly from the "add/remove programs" control panel with no luck.
That is because uninstalling it through the control panel doesn't get rid of everything and, for some reason I can't comprehend, Microsoft (1) knows this, (2) has released Windows Installer Cleanup to make up for the deficiency, and (3) hasn't been smart enough to pre-install the cleanup features into the control panel... but more on how pathetic this company is later.
For now, what I did was I downloaded the Cleanup utility from the link above, Installed it, then opened it (I only found it on the "all programs" sub-menu in the start menu). Once you have it open, highlight these applications:
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Microsoft SQL [/font] [font='Arial','sans-serif']
Server native client [/font]
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Microsoft SQL Server Setup Support files [/font]
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Microsoft SQL Server VSS writer [/font]
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Then click remove. Then restart windows and try to install Disc 2 again. [/font]
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NOTE: You MIGHT need to also use cleanup to get rid of MSXML 6 (that's not the complete name but Windows won't cooperate with me right now so I'm having trouble getting it - isn't Microsoft great? It's no surprise that Bill Gates is one of the richest men on earth! NOT!) AH, there it goes! It is called "MSXML 6.0 Parser"... I *think* that installs along with SQL server and needs to be removed by cleanup as well (that's what I did and it worked) but I'm not certain. [/font]
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HOPEFULLY Windows Installer Cleanup will fix the problem for everyone... somehow I doubt it since this problem has existed for almost 2 years and is all over the internet. GOOD LUCK![/font]