How do I fix a "Couldn't find primary concept for DiagnosisMetadata" error?

[raff (Rafal Korytkowski)]

This is related to

Configuration required: Telephone Number error when registering patient

The error implies that your database tables may not use the utf-8 encoding. Please see mysql documentation on how to fix that.

Metadata was not properly installed in your system. Please do not post new errors until you fix the above.