Are you using EmailXaminer in addition to EmailXtender? If so there's a few extra things that happen.

1. EmailXtract calculates a 'message id' for each message before it is copied to the EmailXtender server. If the message is a duplicate it is not collected. EX further evaluates the message against rules configured by the Administrator.

2. The Shortcut task will also Archive messages unless it has already been Archived by another task or through Journaling.

3. EmailXtract replaces the original mail message with a shortcut. The shortcut will contain the message header and the body.

The message collection process is documented in more detail in the EMC EmailXtender Version 4.8 SP1 Administrator¿s Guide under Chapter 3. To minimize impact on network bandwidth you may consider breaking up the Archive task using date ranges as part of your message selection criteria.

Hope this helps.

Thanks, I did learn from your reply.

No Emaiexaminer will be used (we are about to start using the Emailextender).
To better understand your reply, let us concentrate on the message ID.

What part of the software do this calculation and storing of the id?

Do I need to install any software on the Domino server to run the archive?

If no, can I install anything on the Domino server to make the archiving quicker?

During the Archive task EmailXtract calculates the messageid and stores it in an SQL database. There is nothing required on the Domino server however some pieces must be installed for shortcut resolution.

I am very thankful for everyone that tries to solve my questions. But, sorry to say, you miss the point. I do want to understand at what occasions a mail, stored in my Domino server, is transported over the line to the EmailExtender server. That is all.
Since no software has to be installed in the Domino server, I have guessed that a certain mail will be transported completely 1) when archived 2) when shortcutted. In both cases at least some of it also has to be transported back, because of updates.
Are my guesses correct or are there any tricks performed by EX to transport less data?
The reasons for my concern is that the EX and domino servers are very far from each other.

EX 'transports' the complete message when archiving.
The message is not transported again during the shortcut task unless the message is not already archived.
Does that help?

Be carefull with exclusion/inclusion rules in folders.

When EmailXtender process a message, EmailXtender puts a mark in his properties in the message in mailbox. You can see it with Outlook Spy for example. If you launch a archive task for example, EmailXtender checks this properties to process this message or not.

If you want to process messages again, you must speak with Support.

In the past, I have have problems with exclusion/inclusion rules.

Regards.