>>Starting recently I'm experiencing a weird and annoying issue.
>>
>>Normally I get notifications about the new emails as soon as they are arriving (some sound and the notification shows up).
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>>But starting about a month ago or less I'm experiencing some sort of a delay with notifications and then they start to appear for all messages which came in some interval before which is extremely annoying and distracting (about 10+ notifications coming at once).
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>>Do you know what may have caused this problem and how to fix it?
>
>I use Outlook with Exchange 365 and when I get something like that, I have to restart the application.

That's what I've been doing too. But it's annoying and I believe it only started this behavior recently.

It just occurred to me that it may be a problem in our Exchange server and not something locally.