Running .net2.0 application using .net4.0 framework

We only need to create a new file called xxx.exe.config.
note: xxx.exe is your donet application.

Then fill the following codes to the config file:

<?xml version="1.0"?>
<configuration>
<startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
</startup>
</configuration>