Symptoms

When trying to change nameservers for a Verisign (.com, .net) domain, the following error is thrown:

Nameserver creation or update failed:
ns1.example.com, 2201, Authorization error

or when trying to register/update a SIDN (.nl) domain with nameservers whose glue records have a domain that belongs to another registrar:

Nameserver creation or update failed: 
ns1.example.nl, 2201, A superordinate name server can only be registered by the managing registrar. 

Cause

Registry's logic forbids creating nameserver host objects for domain names that are not in the possession of the registrar that creates them.

In other words, "Authorization error" message pops up when one tries to assign nameservers which contain a domain name that does not belong to one's portfolio.

Resolution

If it is necessary to use nameserver hosts that are not in one's reseller account, consider first creating host objects(domain name - ip address pairs) at the registrar that holds a particular domain name and then updating nameservers at Openprovider account.