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Solution: Use described options.
Please find list of personal notifications in upper right side:
1. To stop a single notification, open it and press Complete in the appearing pop-up window:
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3. To postpone all notifications together, clear notification list and :
And put in Personal settings required periodinterval:
4. If you prefer to switch off all of these notifications at all (and for all users), then go to Administration > Master Data > Notifications.
Choose notification, open it and deactivate:
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