When you get this message, it means the passwords between oneadmin and serveradmin are not in sync or you have the wrong hash in ~/.one/ files and the oned (pgrep -lf oned) service isn't really connecting to anything to get the username it needs.  

"OpenNebula USER name not found, use the ID instead"

We will set about modifying the one file that has the old key.  

The file we want to modify is the ~/.one/one_key with the same password as the *_auth files have after modifying the OpenNebula database as well as other authentication errors in the log file /var/log/one/oned.log (Password in the /var/lib/one/one.db is the SHA1 of the clear text pass you use below) : 

[oneadmin@opennebula01 .one]$ grep e208a *
grep: backup: Is a directory
ec2_auth:serveradmin:MyPass
occi_auth:serveradmin:MyPass
one_auth:oneadmin:MyPass
oneflow_auth:serveradmin:MyPass
onegate_auth:serveradmin:MyPass
sunstone_auth:serveradmin:MyPass
[oneadmin@opennebula01 .one]$ cat one_key
MyPass
[oneadmin@opennebula01 .one]$

Cheers,
TK