Ronie,
Are you seeing, for example, [Main.Alerts.frmAlertProfile_RemindDomain] or [DomainAdmin.frmListSettings_DoNotSet], on certain pages (typically in red)? If so, then the translation XML files are missing that particular entry. To fix, you need to add the entries. For example, you would add <resource name="DomainAdmin.frmListSettings_DoNotSet">Your translation of "Do Not Set" here</resource>
The XML files are located in MailService/Translations/{your language}.xml and SMWeb/App_Data/Translations/{your language}.xml