opendkim-testkey gives error, but no explanation

I'm setting up opendkim on Linux. When I send an email, the dkim does not pass. In doing diagnostics I ran. opendkim-testkey -v -v and it returned, opendkim-testkey: using default configfile /etc/opendkim.conf opendkim-testkey: record 0 for 'default._domainkey.mydomain.com' retrieved opendkim-testkey: load of key 'default._domainkey.mydomain.com' failed why doesn't the key load? I can't detect any errors in /var/log/mail.log.