There was an error reading the rules from the server. The format of the server rules was not recognized.

Question

There was an error reading the rules from the server. The format of the server rules was not recognized." keeps popping up in Outlook.

Answer 1

Which version and build of Outlook are you using? See File, Office Account for the information in classic Outlook.

Switch to the View tab > View settings > General > About Outlook if using the new Outlook.

If you are using classic Outlook, Close Outlook and press Windows key + R to open the Run dialog. type or paste the following into the Open field and press Enter or click OK to restart Outlook. (There is a space before /)

outlook.exe /cleanrules

Outlook supports 3 rules switches - you could try cleanserverrules first:

/cleanrules - this deletes client and server rules.

/cleanserverrules - deletes only server rules

/cleanclientrules - deletes only client rules