.net – Upgrade to 3.5 SP1 & 3.5 Family Update on client systems can break the code

.net-3.5net

I have a server hosting a remoting application using .NET 3.5. It has been running fine. In the last couple of days I have had numerous reports of users not being able to access the application after running the "Microsoft .NET Framework 3.5 Service Pack 1 and .NET Framework 3.5 Family Update (KB951847) x86" update.

I am tempted to run this update on the server – but don't want to cause any problems with my users that have not run this Windows Update.

I can update my application, but I see from other questions on SO that this shouldn't be an issue – as my dev machine does not have SP1 on it, so the app is not using anything that is dependent on SP1.

Any thoughts on what might be happening?

Best Answer

SP1 for .NET 3.5 includes bug fixes and a lot new functionality.
From my experience upgrading from any of the frameworks .NET 2.0 SP1 to 3.0, 3.0 SP1, 3.5
to any higher framework (up to 3.5 SP1 - haven't tried the 4.0 beta) does not break anything.
In fact, .NET 3.5 SP1 is actually based on .NET 2.0 SP1 and adds functionality to it.