Campaign Enterprise can connect to any ODBC compliant database, one that complies with Open Database Connectivity requirements. These include, but may not be limited to the following:

• MS Access
• MS SQL Server
• MySQL
• Oracle

There are three steps to go through before making data available to the end user for actually sending the campaign.

• Set up the database connection
• Select the table and and filters
• Assign it to the end user

Set up database connection:

• Determine your database type. The database connection is dependent on what database you intend to use for your email addresses. Go to connectionstrings.com and get the right connection string for your database. You will need to know the version of your database, the permissions used, the IP address and other information as specified by your database administrator. You may also need a username and password depending on how your database is administered.
  
  Example Strings: 
  Access: Standard Security: Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\myFolder\myAccessFile.accdb; Persist Security Info=False;
  
  Access: With Database Password: Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\myFolder\myAccessFile.accdb; Jet OLEDB:Database Password=MyDbPassword;
  
  MS SQL Server: Standard Security: Server=myServerAddress;Database=myDataBase;User Id=myUsername; Password=myPassword;
  
  MS SQL Server: Trusted Connection: Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
  
  MySQL Standard Security: Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword;
  
  These are just a few examples. Go to connectionstrings.com to find the string for your database.
• In Campaign, log in as the administrator and click the Administration link.
• Click Database Connection Management
• Click Add New Database Connection
  Name it something readily identifiable, "Main SQL Connection" for example
  Select the database type
  Enter the string, with any variables necessary already filled in.
  
  When you save the string, Campaign will automatically test the connection. You may have to tweak the syntax of your string as prompted to successfully connect.
• If you are in a multi-user environment, make sure you assign the users and groups that have access to this connection.
  

Create External Email List:
You can now create a new external email list, using this connection string. All available connection strings will show in the drop down and you would select the one you need for a particular list.

• Click Email List
  
• Click Add New Email List
• Name the list something readily identifiable "Sales Followup" for example
  
• Select External and click continue
  Select the database connection from the list of available connections
  Select the table, SQL Statement option, Stored procedure or use a filter in the project by selecting "From Campaign"
  Match the columns shown, Bounce, Unsubscribe, ID and Email
  Then save the Email List
• Enter a Bounce SQL statement if you want one.
• Set the permissions for this connection
  

There are other options available for more advanced list configuration should you need it. Please contact technical support for more information. The email list will appear in the campaign to address field for those users with permission to connect to this list.

Though this has been written on before it is always good to review from time to time the subject of bounces.  If you send any quantity of email, whether you use your own mail server or a service, the "quality" of your list is extremely important. If your list has a lot of bad emails then it you could be marked as a "bad" sender and lose reputation with the big-boy mail services.

THE PROBLEM: Returned emails do not have a standard format.  Many initially believe that a "returned" email should be the whole email, which would be wonderful, but usually mail servers in the world either stripe down the email to almost nothing or just send back their own rendition.  Overall, you can not rely on either the headers or the body of the bounced message to be able to reliably identify the original recipient, especially if you want to automate the process. Even if you add your own custom headers, it's likely that the bouncing server will strip them when it sends notification back to you.

The only piece of information that will remain intact in a bounce is the return-path email address because at a minimum the email will need to return to that email address. The only way to automate truly accurate bounce catching is to encode the recipient directly into the return path address itself. This would typically be done by overriding your server's default return path address for each outgoing message, using a unique value per recipient, like bounce-XXXXX@yourcompanydomain.com, where XXXXX is some encoded and/or obfuscated representation of the recipient's email address or some other internal identifier.  This is VERPs, or Variable Envelope Return Path.  Campaign Enterprise v12 uses VERPs to process bounced emails.

Be sure to check out the Campaign Enterprise Version 12 Documentation for more information on how bounce handling is done in Campaign Enterprise v12.