The column header "DomainAdmin.frmAliases_InternalOnly" shows if that particular entry is missing from the en.xml file. Make sure that the following entry is in the en.xml file:
<resource name="DomainAdmin.frmAliases_InternalOnly">Internal only</resource>
That file is located here (assuming default installation):
C:\Program Files (x86)\SmarterTools\SmarterMail\MRS\App_Data\Translations\en.xml
C:\Program Files (x86)\SmarterTools\SmarterMail\Service\Translations\en.xml