Filed under: vmware
UPDATE: This issue has been resolved in vSphere Update 1 link: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1011329
If you are reading this you probably found out that vSphere Client 4.0 is not (yet) running on Windows 7 RC or RTM
Luckily there is a way to make it work.
The error looks like this:

Error parsing the server “name” “clients.xml” file.
First the credits. Big Thanks to FTUBIO from the VMware Communities (link) For supplying this solution.
1. Obtain a copy of %SystemRoot%\Microsoft.NET\Framework\v2.0.50727\System.dll from a non Windows 7 machine that has .NET 3.5 SP1 installed. You can find it in the vclient_on_w2k7_hack.zip file on the bottom of this post.
2. Create a Lib folder in the Windows 7 machine where the vSphere client is installed and copy the system.dll file from step 1 into this folder. Create the folder lib under the vSphere client launcher installation directory (%ProgramFiles%\VMware\Infrastructure\Virtual Infrastructure Client\Launcher\).
3. Copy (and overwrite) the VpxClient.exe.config from the zip file in the bottom of this post to the %ProgramFiles%\VMware\Infrastructure\Virtual Infrastructure Client\Launcher\ folder
note: You might have an issue with the UAC settings and are not allowed to replace files in the Program Files folders. In this case make sure that you run the explorer as administrator (Start -> All programs -> Accessories -> Windows Explorer. Right Click “Run as administrator”).
4. Create a system variable devpath with a value of C:\Program Files\VMware\Infrastructure\Virtual Infrastructure Client\Launcher\Lib
assuming your default install path is C:\Program Files
5. Reboot your machine and start vSphere client (For some people a reboot was not nescesary)
Note1 that this workaround bypasses the normal .NET Framework loading mechanism so that assembly versions in the DEVPATH folder are no longer checked. Handle with care
Note2 If you use Windows 7 64-bit replace “Program Files” with “Program Files(x64)” in all cases

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