Does a VSTO add-in require the .NET 3.5 framework?

Hello all,

I have written a VSTO add-in for Excel 2003/2007, which works great on a machine where the .NET framework 3.5 is deployed.

Unfortunately, one of the users works in an IT-restrictive company, which has "not tested" the 3.5 framework, and is reluctant to install it.

I tried to rebuild the add-in targeting the 2.0 framework, removing all 3.5 dependencies. Yet when I deploy it, it complains that the 3.5 framework is required, even though I cannot find a dependency in my project.

Does anyone knows if 3.5 is required, maybe through the PIA assemblies, or some other component I would have overlooked? Has anyone succesfully deployed a VSTO add-in on a 2.0 machine?

Thanks in advance for any light on the topic,

Mathias

Mathias,

See if my following blog post will resolve it:
http://xldennis.wordpress.com/2008/07/31/vs-2008-com-add-ins-and-launch-conditions/

Dennis,

You are my hero - it worked like a charm, and... you saved my week-end :) .

This is a seriously annoying bug though: when you specify that the target is 2.0, you would expect the launch condition to be updated, or at the very least to display some error message during the build!

Thanks again,

Mathias

Mathias,

You're welcome and it's remarkable that this "feature" still exist after SP-1 to VS 2008 was released. Let's hope it's gone with SP-2 or with VS 2010.