Issues if FSMO roles are not functioning properly

If one or more FSMO roles are not functioning properly ,there may be a lot of issues in the Domain enviornment. Let me note down important ones  among them

1. Domain Naming Master

1. Can't add or remove a domain - Changes to the namespace need this role holder.
2. Can't promote or demote a DC - Changes to the namespace need this role holder.

 

1. Schema Master
1. Can't modify the schema - Changes to the schema need this role holder.
2. Can't raise the functional level for the forest - This role holder must be available when the raising the forest functional level. 

      3  PDC Emulator

1. Users can't log on - If system clocks become unsynchronized, Kerberos may fail.
2. Can't change passwords - Password changes need this role holder.
3. Account lockout not working - Account lockout enforcement needs this role holder.
4. Can't raise the functional level for a domain - This role holder must be available when the raising the domain functional level.

       4   RID Master

1. Can't create new users or groups - RID pool has been depleted.

        5  Infrastructure Master

1. Problems with universal group memberships - Cross-domain object references need this role holder.