GeoNetwork CSW Harvest Error - "gmd:MD_MetaData, csw: record" is not a valid value for QName

"gmd:MD_MetaData, csw: record" 

Well, the error message is correct the quoted text is not a valid QName, as we can see from its definition:

QName              ::=   PrefixedName | UnprefixedName
PrefixedName       ::=   Prefix ':' LocalPart
UnprefixedName     ::=   LocalPart
Prefix             ::=   NCName
LocalPart          ::=   NCName

and

NCName             ::=   Name - (Char* ':' Char*)  /* An XML Name, minus the ":" */

Reference https://en.wikipedia.org/wiki/QName

i.e.

We have a PrefixedName, the prefix is gmd, we have an :, the LocalPart is therefore MD_MetaData, csw: record which should be an NCName but it is invalid because there is a colon after the csw.