Some applications do require a newer version of .NETCF. You see, I have uploaded .NETCF v3.5
for you. I have also uploaded a small application, .Net Configuration
. Install both of them on your device, and run '.Net Configuration'. I'll tell you how I configured it on my device, and you decide if it fits you needs: In the 'Device Policy' tab, I selected '3.5.7283' and tapped on 'Apply'. However I know that the mobile calculator doesn't quite like v3.5, for what in the 'Application Policy' tab, I selected '\Windows\MobileCalculator.exe' , assigned it to '2.0.7045' (my version of the default .NETCF v2;0 - yours might be slightly different) and tapped on 'Apply'. Tapped on ok to leave the application, and restarted my device.
Of course you can do differently: set your 'Device Policy' to v2.0 (as it has ever been) and assign the application, which is issuing errors with v2.0, to v3.5.
Hope it works for you.