Duplicate incoming. What to do?

Question

Outlook

Hello.
Broken head already, no ideas.
We have a user who is sitting in outlook 2013. Exchange, caching is off (blocked).
The user creates a rule to transfer letters to any folder + "display a notification on the desktop". The letter comes in duplicate. We noticed that the problem occurs only when the alert is on, without it everything is ok.
What we tried: recreate the mail config; deletion of all rules (there were no duplicates, however), including those on the server; different PCs; clean up all the tempos.
The problem is only with one user, others do not have it, and it is not possible to repeat it at home either.

Answer 1

If alerts are needed for all folders, you can create a separate rule "display an alert" for all incoming letters in a row, and after it, arrange them into folders with the following rules.