If you are getting this through the Digital Collection Gateway registration page, please reach out to OCLC Support and provide either a screenshot of your registration form or your library's OCLC Symbol, email address, and your WorldCat.org username.
If you are getting this failure when clicking on the CONTENTdm > Server > Harvesting > WorldCat Sync > Register button, please send us your CONTENTdm site number, your email address and your WorldCat.org username.