UPDATE: November 10, 2015: this workaround is not needed if you are using the 64-bit OS version of ERwin Data Modeler which was introduced in version r9.64 and later.
Using the r9.x MartUpgrade utility, when the user gets to the Select Models link, they get "Unhandled Exception has occurred in your application. System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt" and the MartUpgrade is not able to proceed.
You are most likely running the MartUpgrade on a 64 bit Operating System and did not completely follow the instructions in other Article 2902, especially step 3. You most likely lacked the privileges on your PC to execute step 3 and ran into the error "the module was loaded but the call to dllregisterserver failed with error code 0x8007005", or similar.
We have since updated article 2902 with a way to run step 3 on less privileged Windows system via Administrative mode. Please see "NOTE 2" in other article 2902 and then follow steps 1-4 again completely which should resolve the problem. Here is the text from NOTE 2 from article 2902 for your convenience:
NOTE 2: If you are following step 3 're-register the r8 and r9 EAL component' above and you get the error, "the module was loaded but the call to dllregisterserver failed with error code 0x8007005", or similar, that means you lack the privileges to run those commands. The solution is to run the same command in Administrator mode. The way to do that is to paste or type the string into the Run or Search box (as usual) and then Hold Ctrl + Shift and press Enter. That will execute the command as Administrator mode now allowing the registration to complete successfully.