Need a portable "What version of .Net do you have installed?" utility that you can even redistribute? Check out the .NET Version Detector XI

Windows 7 Hacker - How To Tell Which Version of .NET Framework I have on My Computer

"A .Net written application requires a suitable version of .Net Framework installed that is compatible with the one used in the application. So sometime it’s quite useful knowing which version of .Net installed on your computer before going ahead loading a .Net application. Normally, you can find out from Programs and Features window in Control Panel on Windows Vista and 7, or Add/Remove Programs on Windows XP. But, it does feel tedious sometimes.

.NET Version Detector is a free portable utility that gives information on the different versions of Microsoft .Net framework that are installed on a particular machine.

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The author of .Net Version Detector also allows for a vendor to bundle the tool with their application without a fee so that the application bundled with can easily get some generic and accurate information on the frameworks."

.NET Version Detector XI

ASoft .NET Version Detector is a lightweight tool that gives information on the different versions of Microsoft .NET that are installed on a machine.

If a certain version isn't on the machine, you can simply follow the link that .NET Version Detector suggests, so it is easier for the novice user to find the runtimes.
Also detailed information is given on where the .NET Frameworks are installed with links to the directories.
The details can easily be copied by a user, to paste in a mail.
.NET Version Detector is a native application, which means it isn't dependent on any version of .NET to run.

.NET Version Detector is a handy tool for vendors of .NET applications also.
Knowing which versions a user has installed and where they are located on the hard drive.
ASoft allows for a vendor to bundle .NET Version Detector with its application (for free!) so that it is easier to get some generic and exact information on the frameworks.
But before doing so, contact us first!

New Features:
- Supports commandline option to export data to file (txt/xml) and not show the user application

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I have so needed something like this, something that's very user safe and simple.

A couple things I liked;

a) Portable

b) Easily email'able (via the copy paste)

c) Makes getting and installed the frameworks easy too;

d) Price(free)

e) That  I could bundle this for free with my apps as needed.