Problem

Tekla Structures ISM Mixed Mode Assembly Error occurs when trying to create a repository from a Tekla Structures v.20 model (Tekla Structures version 20.0, with ISM Tekla plug-in and the latest Structural Synchronizer.).

“Mixed mode assembly is built against version v2.0.50727 of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information”

Solution 

Resolution requires adding the following section to Tekla Structures configuration file. TeklaStructures.exe.config found in the same folder as the TeklaStructures.exe

<configuration>

  <startup useLegacyV2RuntimeActivationPolicy="true">

    <supportedRuntime version="v4.0"/>

  </startup>

</configuration>

So the bottom lines of the file become:

</runtime>

<startup useLegacyV2RuntimeActivationPolicy=”true”>

<supportedRuntime version=”v4.0” />

</startup>

</configuration>

More information can be found here:

http://msdn.microsoft.com/en-us/library/bbx34a2h(v=vs.110).aspx

http://stackoverflow.com/questions/1604663/what-does-uselegacyv2runtimeactivationpolicy-do-in-the-net-4-config

The Tekla users should acquire the Tekla 20 ISM plug-in from Tekla. It is available through the Tekla Extranet (Login required).

ISM Tekla Plug-in