I'm sorry, but this is ridiculous.
OP: I'm having a specific error while using the v6 migration tool
Response: Did you test version 6 to make sure you like it?
OP: No, but sure maybe I'll test it out
Response: (Continued talk of how different version 6 is)
Then finally, another response other than just talking about how different the new version is appears, only to basically say RTFM, and then finally recommends just doing a clean install.
Seriously? This is a question about a *specific* error that is very clearly presented simply by running the migration tool and trying to do a simple export of v5 configuration data.
Oh, by the way. I am getting this error too. And no, I haven't run a test virtual environment for 6 months with a new version before simply attempting to export configuration data from the old version. And yes, I have read the instructions completely. And no, I don't have some complex environment or a huge number of clients. If I have to do a clean install it's not the end of the world, but this is very unprofessional to have no working upgrade path.