Here are a few items to consider when troubleshooting vCenter permissions. There are times when you will experience strange errors when permissions are not applied correctly, for example, user not authorized or incorrect username/password when the user tries to login. This can happen when the user has permissions assigned in a variety of levels. Check all levels (vCenter object, Cluster, and the Data Center), then make sure read-only role is set up correctly at the cluster level. To avoid issues like these, be sure that the level of permissions across your users is consistent. Pay close attention to the top layers of permissions. When giving account rights to the vCenter object, make sure it has vCOps User access.