Okay....Why Won't Windows .NET Framework 3.5 Install?

[DaveM]

My computer crashed early this past week and for the first time since I bought it in early 2006, I had to do a complete restore of the operating system. Which, of course, has meant wading through over 200 updates and who knows what all. Everything has gone smoothly, though it's been a pain in the ass, but now Windows Update is telling me I need Microsoft .NET framework 3.5, and it simply won't install. I have tried a few tricks and suggestions from the net, but none has made any difference. Has anyone else run into this? I can't figure out what could be clocking the install.

[richthelandlord]

The usual issue is that .net framework 4 is already installed.

These days it's normal to have both, but they need to be installed in the right order or they won't play nicely.

The same applies on Patch Tuesdays if .net has patches... they're always worth doing separately afterwards and in the right order of it often hangs the lot.

[DaveM]

Thanks--my difficulties began with Update Tuesday, and I suppose something hasn't gone in in the order Windows wants it to. All hail the mighty wisdom of Windows!

[richthelandlord]

Thanks--my difficulties began with Update Tuesday, and I suppose something hasn't gone in in the order Windows wants it to. All hail the mighty wisdom of Windows!

It was almost certainly a problem installing .net updates that caused your woes... my machine had updates for both .net3.5 and .net4 included in the mess.

They generally install ok automagically in 64-bit versions, but 32-bit versions are as cranky as all hell...

Much safer to uncheck any .net updates and do everything else first regardless of windows version, restart and then do .net 3.5, restart again before doing .net4

Yes, that's a pain in the fundament - but not as much as rebuilding your machine...

[DaveM]

I wound up using a "cleanup tool" which spent nearly half an hour rooting out all of the bits and pieces of various .Net installations which were apparently all over my hard drive. After that, 3.5 installed and updated just fine--as best as I can tell, I had 2.0 and a bunch of failed installs. Now I suppose it will be after me to install 4.0 but the computer is running beautifully at the moment. I don't much feel like "fixing" any more!