I completely forgot to document this down after having overcame it a couple of weeks back, so I better log it down even though I still haven't done that last bit of verification testing.
It seems that a very low number of Windows Vista systems will encounter a show-stopper error that prevents .NET Framework 1.1 from successfully installing. It will fail at almost the very last stage of registering System.EnterpriseServices.dll
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RegSvcs.exe - Common Language Runtime Debugging Services
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Application has generated an exception that could not be handled.
Process id=0x9a0 (2464), Thread id=0xf70 (3952).
Click OK to terminate the application.
Click CANCEL to debug the application.
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OK Cancel
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Searches based on that error message will land you, with a 99.999% money-back guarantee, at one of the following entries in Aaron Stebner's blog
http://blogs.msdn.com/astebner/archive/2006/07/06/658484.aspx
http://blogs.msdn.com/astebner/archive/2006/01/08/510677.aspx
http://blogs.msdn.com/astebner/archive/2007/02/04/error-installing-net-framework-1-0-and-1-1-on-windows-vista-caused-by-data-execution-prevention-dep.aspx
if not, it is likely be a newsgroup or mailing list discussion that leads to one of those anyway. But I have stated "very low number" because none of those issues documented worked for my machine as well as a colleague's. Disabling Vista's unsexy UAC did not give joy either. A couple of others in the Internet cried with the same tears over no solution.
It wasn't until an overseas colleague of ours that pointed us to a secluded MSDN forums thread did I finally come across a post of his that links to yet another blog entry of his, teaching how to introduce a breakpoint during installation. This one magic trick that stealthily escaped Google's radar (as well as way out of "range" for MSN Live), is the one that beats the above problem. .NET Framework 1.1 gets installed past System.EnterpriseServices.dll.
The reason why I did not write this down immediately was because I encountered yet another error during the installation,
Removing backup files
File: E:\... \migpolwin.exe –migrate 1.1.4322.1.0.3705
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migpolwin.exe - Common Language Runtime Debugging Services
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Application has generated an exception that could not be handled.
Process id=0xd10 (3344), Thread id=0x4e0 (1248).
Click OK to terminate the application.
Click CANCEL to debug the application.
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OK Cancel
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even though the installation was marked successful and registered in the Programs listing. I was waiting to find a slot of time to install a variety of .NET 1.1 programs to test the stability of the installation, but eventually lost out to the labyrinth of life (that was a testbed machine after all). This will suffice for now.