ArticlesArticles Most Popular ArticlesMost Popular Articles
RSS Feeds
DrillDown Icon Table of Contents
DrillDown Icon 2020 Official Holidays & Support Schedule
DrillDown Icon IMPORTANT: End of Life of SHA1 on Windows Server 2003
DrillDown Icon IMPORTANT: Supported Operating Systems
DrillDown Icon PLEASE READ: Our Update Server IPs Have Changed
DrillDown Icon Support
DrillDown Icon modusGate for Microsoft Azure
DrillDown Icon modusCloud
DrillDown Icon Alleviating Spam – Best Practices
DrillDown Icon directQuarantine Technical Information
DrillDown Icon modusMail & modusGate Technical Information
DrillDown Icon Documentation & Release Information
DrillDown Icon Known Issues (non-release related)
DrillDown Icon Configuration Information
DrillDown Icon modusGate & modusMail
DrillDown Icon modusGate Only
DrillDown Icon How-to: Perform a Backup/Restore on a modusGate Appliance
DrillDown Icon How-to: Integrate modusGate with a PGP Gateway
DrillDown Icon How-to: Reset a ModusGate Appliance to its Original State
DrillDown Icon How-to: Encrypt ModusGate User List Population and Authentication Requests
DrillDown Icon How-to: Install ModusGate v4.4 on Small Business Server 2003
DrillDown Icon Info: Appliance Cannot Access the ModusGate Console or System Health Panel
DrillDown Icon Info: ModusGate Appliance Cannot be Reached after Hooking up to the Network
DrillDown Icon How-To: Configure ModusGate with Specific OpenLDAP Server Attributes
DrillDown Icon How-To: Configure ModusGate with Sun One Open Directory for Sun Email Servers
DrillDown Icon Info: Mailbox Verification vs. Mailbox Authentication
DrillDown Icon How-To: Deactivate the Mimicking of Active Directory’s "Disabled Accounts" in ModusGate
DrillDown Icon Info: Forward Lookup / Pre-auth Options in ModusGate
DrillDown Icon How-To: Change the IIS Port on the ModusGate Appliance
DrillDown Icon How-To: Configure ModusGate with an Exchange/Outlook Junk Email Folder
DrillDown Icon How-To: Deploy ModusGate with Exchange/LDAP Servers
DrillDown Icon How-To: Deploy ModusGate with Groupwise
DrillDown Icon How-To: Deploy ModusGate with Lotus Domino 5 & 6
DrillDown Icon How-To: Deploy ModusGate with Postfix
DrillDown Icon How-To: Deploy ModusGate with Qmail
DrillDown Icon How-To: Deploy ModusGate with Sendmail
DrillDown Icon How-To: Prevent the Accumulation of Invalid User Names with Remote Exchange Server
DrillDown Icon How-To: Test POP3 Authentication with ModusGate
DrillDown Icon Info: Modusadm will not start while installed on Exchange 2013.
DrillDown Icon How-To: Upgrade NEP to modusGate \ modusCloud
DrillDown Icon How-To: Deploy ModusGate with Azure
DrillDown Icon modusMail Only
DrillDown Icon SQL Server Information
DrillDown Icon MySQL Information
DrillDown Icon Security
DrillDown Icon Sieve
DrillDown Icon Spam and False-Positives
DrillDown Icon Statistics and Monitoring Section
DrillDown Icon Web Components
DrillDown Icon Troubleshooting
DrillDown Icon Hardware & OS System Requirements
DrillDown Icon Tools
DrillDown Icon Other Product Technical Information
DrillDown Icon Professional Services
DrillDown Icon Newsletters
  Email This ArticlePrint PreviewPrint Current Article/Category and All Sub-Articles/Categories
How-To: Prevent the Accumulation of Invalid User Names with Remote Exchange Server


Product: ModusGate

Version & Build: 4.0 + up




Some customers use ModusGate to filter mail for an Exchange 2000/2003 server that is outside of their own network.  Because these clients have no control over the security of the external Exchange server, they use a simple SMTP connection which does not involve validation (forward lookup) of the recipients' manes.  As a result, there is an accumulation of invalid user names in the Console which, in turn, can cause licensing errors if the mailbox limit is reached.



THe best solution is to use one of the forward lookup options by connecting to an LDAP or Active Directory server, as outlined in the ModusGate manual.

However, some people have security concerns such as not opening up Port 389 to outside traffic.  We offer the following alternatives:

1. Install an Active Directory DC SSL Security Certificate on the Exchange server.  On the ModusGate server, go to Connections - Properties - General and configure the following:

  • For Automatically populate user list and Authentication Requests, select Exchange 2000+
  • For both settings, enable Use SSL/TLS
    • If using an LDAP or standard Active Directory connection, use Port 636
    • If connecting to the Global Catalog on the AD server, use Port 3269
  • Click Apply 
  • Stop and Start the SMTPRS service

The following links provide information about installing the Domain Controller certificate and how to Enable LDAP over SSL:


2.  Use VPN for a secure connection between the ModusGate and Exchange servers.  Afterwards, configure an LDAP connection on Port 389 to authenticate the users.


Modified 12/20/2006
Keywords: Exchange, invalid users, license exceeded, SSL, VPN, LDAP, Active Directory
Article ID: 1414