silently installing .Net 3.5

Very good info about the installation requirements of .Net 3.5 - http://www.msfn.org/board/NET-Framework-35-Silent-Installer-t108344.html

reasons why the .Net 3.5 framework installer might want to still go out to the web - http://blogs.msdn.com/astebner/archive/2008/07/17/8745415.aspx

.Net 3.5 offline installer - http://download.microsoft.com/download/6/0/f/60fc5854-3cb8-4892-b6db-bd4f42510f28/dotnetfx35.exe

According to this forum listing you should be able to run a local copy of the offline .Net 3.5 framework installation from the command line with the /q for a silent installation. In testing this it looks like its good to go. I've been working with this line in my .Net installer component for past NSIS installations (with older .Net runtime installations):
ExecWait '$TEMP\dotnetfx.exe /q /c:"install /q"'

so on the regular command line this would look more like:
>dotnetfx35.exe /q /c:/"install /q"

With the older .net installation it was easy just to store it inside of the setup.exe I was compiling, extract it to the temp dir, and run it from there. We've been using .net 2.0 with this approach, when the .net installation was a mere 20mb. Now the offline .Net 3.5 sp1 release is closer to 200mb. So storing the .net installation in the setup.exe only adds time to the installation and wastes considerably more hard drive space on the target deployment machine for installation purposes only (once installed, the .net installation doesn't need to remain on the machine).

So I'll be revising a couple of lines in my custom NSIS .Net install module.