I want to enable DupeBlocker for the User object precisely because I think it would be really helpful for detecting and merging duplicate user records created by the same individual in my Customer Community.  However, when I tried enabling DupeBlocker for the User object in my Production org, I got the below very nasty error message that I can't figure out how to parse.  Clearly, it has to do with the unit tests related to Communities, but I don't even know where to get started in solving the problem.  I'm guessing that 99% of the long error message is being generated as a result of one or two errors that probably make up 1% of the error message.  Can anybody help me find that nugget and figure out what I need to change with my unit tests?  

Thank you in advance for any help you can provide!


Enable Object Error

Unexpected error encountered:

<details 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xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/><numLocations>9</numLocations><numLocationsNotCovered>5</numLocationsNotCovered><type>Trigger</type></codeCoverage><codeCoverage><id>01pF0000003EIR8IAO</id><name>ChangePasswordController</name><namespace xsi:nil="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/><numLocations>6</numLocations><numLocationsNotCovered>0</numLocationsNotCovered><type>Class</type></codeCoverage><codeCoverage><id>01pF0000003jIJpIAM</id><name>Q_A_redirect</name><namespace xsi:nil="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/><numLocations>0</numLocations><numLocationsNotCovered>0</numLocationsNotCovered><type>Class</type></codeCoverage><codeCoverage><id>01pF0000003EOplIAG</id><name>CommunitiesSelfRegConfirmController</name><namespace xsi:nil="true" 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