Getting error "An entry with the same key already exists." when creating a new relying party trust

I am trying to add a new relying party trust using ADFS 3.0.  Everytime I add the metadata url I get "An entry with the same key already exists".  I've tried using powershell and get the same result.  I have looked in the event viewer as well as enabled ADFS tracing and am getting no errors I can use to troubleshoot.  Is there a different log somewhere that would lead me to what is wrong?  I am suspecting the xml file could be at fault, but this 3rd party has others using this metadata url with no issues.  I would rather not post their XML file if possible.  They are looking into the issue as well I just wanted to know if there was a another spot I could look for logs.  Thanks a lot.