Hi @Nuno Dias ,
Welcome to our forum!
Do other users encounter the same issue?
Please follow the below steps to troubleshooting:
1.Please first check and confirm the rules are enabled.
2.Are these rules based on client? If so, please log in to web mail and create the same rule and open Outlook desktop client to check if there're any differences.
3.If the web-side rule can work, considering the send/receive settings file (SRS file) is damaged, please try to reset the SRS file to check if there're any differences. (Go to C:\Users%username%\AppData\Roaming\Microsoft\Outlook>Rename the Outlook.srs file to Outlook.srs.old>restart Outlook)
4.If the above doesn't help, considering that the rules are corrupted/damaged, please try a command to delete all rules: win+R> type: outlook.exe /cleanrules.
Hope the above help!
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