While installing/upgrading the SEP Server installation is interrupted with following error message:
“"Error 1923. Service 'enterprise$sep' could not be installed. Verify that you have sufficient privileges to install system services...”
1. If any domain account is configured as service identity, make sure that the account is local administrator.
2. Make sure that the user running installer is local administrator.
3. Abort the installation, restart Windows. Try again.
Note that “Windows Restart” is REQUIRED in order to fix the issue.