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Open the Configurator > Configuration > Schedule.xml
Edit the cron-expression of the following jobs so that they are not run while the user synchronization is ongoing: UnreadConversationMessagesNotificationJob, EmailJob, screenShotsJob, CleanUpJob
You can use a CRON expression editor to define a period when the services will not be running.
See example below how to pause it between 2 AM and 4 AM
Leave time for export jobs to complete before the user synchronization begins
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