I keep having to look this up every couple of months. Microsoft support have described how to find out.
From the article:
Versions of the .NET Framework
There are currently three released versions of the .NET Framework. The releases have the following version information.
| .NET Framework version |
Revision | Version |
| 1.0 | Original RTM .NET Framework Service Pack 1 .NET Framework Service Pack 2 .NET Framework Service Pack 3 |
1.0.3705.0 1.0.3705.209 1.0.3705.288 1.0.3705.6018 |
| 1.1 | Original RTM .NET Framework Service Pack 1 .NET Framework included with Windows Server 2003 32-bit Service Pack 1 |
1.1.4322.573 1.1.4322.2032 1.1.4322.2300 |
| 2.0 | Original RTM | 2.0.50727.42 |
Note The Microsoft .NET Framework 1.1 is included with the 32-bit version of Microsoft Windows Server 2003.
Note This information should be used as a general guide for determining which versions of the .NET Framework are installed on a computer. Also note that files that have a later version listed may be files that were shipped as part of a hotfix or a hotfix rollup package. The hotfix .NET Framework file versions are outside the scope of this article.
Determine which versions of the .NET Framework are installed on a computer
The easiest way to determine which versions of the .NET Framework are installed on a computer is to locate the %systemroot%Microsoft.NETFramework folder. You can paste the listed address for the Framework folder into a Windows Explorer address bar to navigate to the Framework folder. The three released versions of the .NET Framework are contained in the following folders:
| – | v1.0.3705 |
| – | v1.1.4322 |
| – | v2.0.50727 |
Note If you see other directories that have a vN.N.NXXXX format that are not listed in this article, the versions may be beta versions or pre-released versions of the .NET Framework. Those versions are outside the scope of this article.
To determine which versions of the .NET Framework are installed on a computer, follow these steps:
| 1. | Open any one of the folders in the previous list, and then locate the Mscorlib.dll file. |
| 2. | Right-click the file, and then click Properties. |
| 3. | Click the Version tab, and then note the file version. |
| 4. | Use the previous list to determine which version of the .NET Framework is installed on the computer, and then click OK. |
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