I notice some programs specify a particular .NET Framework in order to function properly (eg., ASv6.5 needs NET v1.1). Checking the Microsoft update site it appears we're up to version 3.5. Couple questions then: 1) Is it advisable to continually update .NET?2) If so, are the earlier versions subsumed by the later versions?, and 3)Is addon software (payware aircraft/scenery)written with a specific .NET Framework, and can having the "wrong" .NET cause cliches in either FS9 or addons?Thanks!F15Driver

Feel free to continue to install whatever the update site has to offer. There's no harm in it.The .NETs coexist. Have a look in the following folder and you'll see separate folders for the different versions: %systemroot%Microsoft.NETFramework (Start > Run).I have up to 3.0, all programs that need a .NET (version) work and I have no other issues.

MikeThanks...I had both NET 1.1 and 2.0 installed and apparently working harmonously together until I had to reinstall FS9...and of course, all the addons. As I was reinstalling AS6.5, I could not get Active Sky Graphic module to work (kept getting XP fatal error messages) until I uninstalled both NET 1.1 and 2.0 and reinstalled ONLY .NET 1.1. ASG works fine now.I've also read in Just Flight Forums that Professional 757 works better (less buggy) when only .NET 2.0 is installed. Thus my question--I had always believed, like you, there is a peaceful coexistence between .NETs but now I'm not convinced.F15Driver

Who's to say the 757 isn't the problem and not .NET? ;-) I do have ActiveSky and never had any problems.What was the reason you had to reinstall FS9? Perhaps there were issues beyond FS9. Reinstalling FS9 may have fixed FS9, but not those deeper problems.There have been stories about .NET for years. I find them entertaining, but my personal experience tells me a different story.

I think I would look for problems first in the development environment used to create the addon before I would look at the user's runtime.scott s..

I reinstalled FS9 because of a conflict with Lock On Modern Air Combat (LOMAC). I should have partioned the HD so that LOMAC would occupy a "separate" block, but I did not. After playing LOMAC for about a week (with TrackIR--awesome!), I began having escalating CTDs of FS9 to the point it wouldn't even load after clicking the icon. I would hear a pinging sound as well so I suspected sound files or sound card corruption (again this only began when I started playing LOMAC--which is a fabulous game--just on my system setup, there happened to be a conflict).I uninstalled LOMAC, but FS9 would not load--I considered just deleting FS9.CFG--but decided to uninstall and reinstall FS9 completely so that I'd have a fresh baseline.I've been able to install all the .NETs as well now and can load AS6.5 engine and ASG with no problems. I believe I skipped .NET 1.1 and went directly to 2.0--that caused ASG not to load.One lesson, I keep learning over and over again, is to save a current version of your FS9.CFG and write down all those tweaks you've made (somewhere).Thanks again!F15Driver