When you update user's Outlook profile using slow connections, CPUU performance may appear to be quite low. Sometimes it may take several hours to update a single profile. How to avoid these significant delays during Outlook profile updating?
If you're using legacy mailbox synchronization agents, i.e., Mail Source Agent and Mail Target Agent, Remote Mail Collection needs to be utilized - it's designed specifically for the slow link scenarios. For more information about processing mailboxes in Remote Mail Collections and preserving the OST files please refer to Migration Manager for Exchange User Guide at https://support.quest.com/technical-documents/migration-manager-for-exchange/8.14/user-guide/16#TOPIC-711660 and Updating Client Profiles documentation at https://support.quest.com/technical-documents/client-profile-updating-utility/5.7.8/administrator-guide.
If you're using Migration Agent for Exchange (MAgE) which doesn't provide an option to preserve OST files, there are still some ways to further optimize CPUU performance explained below.
While being updated by CPUU the longest to process are the so-called Nicknames or Autocomplete hidden messages in Outlook 2007 or later stored in the mailbox itself. In Outlook 2003 and earlier versions these were stored in NK2 files. However, Outlook 2003 and earlier versions are no longer supported by Microsoft or CPUU.
When configuring CPUU with CPUU Configuration Wizard you can make it skip this function. To do that:
1) In CPUU Configuration Wizard on the Features page select Nick files from the list of processed features and click Change button.
2) In the Select Processing Option dialog that appears select Skip option and click OK.
Alternatively, you can modify the existing CPUU.ini file so that Skip parameter is set to Nicks (Skip=Nicks) or Remove parameter is set to Nicks (Remove=Nicks).
Please note: Any of the above ways will lead to no autocomplete e-mails in the target mailbox profile.
So the users may want to reassign their old Stream_Autocomplete_... file to their new profile. There are a lot of ways to do so. One of the ways is described in https://www.msoutlook.info/question/backup-and-restore-autocomplete