This post from Dynamics Confessions blog, informs us about Incompatibility of Dexterity 10.00.320 Build with .NET Framework 3.5SP1.

Those who are working on similar lines, have a look at this article and be informed on what needs to be done in such scenarios.

NOTE: Download Dexterity 10.00.324 Build separately from PartnerSource and install it as soon as you apply GP SP4 on Dexterity. Because this particular Build 324 is the actual SP4 for Dexterity Common Components and Dexterity itself.

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