labview 2009 .NET frame work error

[EZT]

We have Labview 2009 on a WinXP computer.  Everything seems to work okay when running a VI to control some hardware except the computer crashes occasionally and labview seems to run abnormally slow.  We are actually beginning to think it's a labview issue, especially since we get the attached error message when opening labview.  We are running .net framework version 3.5 or 4.0 (one of the two, i can double check that if it's important).  Is Labview 2009 not compatible with newer versions of the .NET framework?  We need the newer verison to run another program so we can't down grade to anything older.  Any suggestions?

-Eric

[Air_Frantz]

The error you are seeing when launching LabVIEW is probably caused because of the version of .NET you have installed.  LabVIEW does an initialization check for whether .NET is installed, and this checks a flag called GetCORVersion which existed in .NET 2.0 and 3.5 but was deprecated in .NET 4.0.  The solution is to manually install .NET 2.0 (as it is likely the one missing). If that doesn't work you may need to also install .NET 3.5 if it is not already present.  You can install multiple .NET version on the same computer so you would not need to downgrade.

I don't believe this is what is causing the problems you are seeing with slow behavior and crashing.  If you think that LabVIEW is causing this, however, your best bet would be to try to uninstall/reinstall LabVIEW on the machine as it may have been corrupted at some point.

[EZT]

Great, thank you for the info.  We will try what you are suggesting.