Is .Net framework free for commercial use?

We have a client who wants us to prove him that we have the right to distribute the .Net fra开发者_如何学Pythonmework along with our application.

Can someone help me out? Does Microsoft have any link where they clearly say it is free to use for commercial purposes?

http://msdn.microsoft.com/en-us/library/aa480243.aspx

Note If you choose to use the Dotnetfx.exe or redistribute it with an application created by you, you must have a valid licensed copy of the Microsoft .NET Framework SDK version 2.0 (or Visual Studio 2005) and any use or distribution of Dotnetfx.exe is subject to the terms of the end user license agreement you received with the Microsoft .NET Framework SDK version 2.0, or Visual Studio. If you do not have a validly licensed copy of the Microsoft .NET Framework SDK version 2.0, or Visual Studio, you are not authorized to use or distribute Dotnetfx.exe."

Would that be sufficient to demonstrate to your client?

The files that you are legally entitled to redistribute are listed in the redist.txt file in your Visual Studio install directory. Yes, the .NET installers, like dotNetFx35setup.exe are included in that list. You could perhaps send a copy of that file to your client.

It's not a true installer, it is a bootstrapper that downloads the actual bits from a Microsoft server. Which is a wise approach, you definitely don't want to distribute a version that predates the last security update. Doesn't happen often, but there was one for 3.5 SP1 just two months ago. Clients do not like getting stuff installed that has documented security issues.

Frankly, including anything in your installer that includes .NET bits is starting to make less and less sense. Especially for .NET 4.0. It is small, ~55 MB vs ~350 MB for .NET 3.5 SP1. By virtue of its prerequisites, it requires a recent Windows service pack. XP SP3 for example. You definitely don't want to get in the business of distributing Windows service packs. State your software's prerequisites clearly, requiring .NET to be pre-installed is defensible, just as requiring a minimum Windows version and SP level. Especially with a client that hassles you.