For Outlook Rules on Exchange, I get this error: There is not enough space on the Microsoft Exchange Server to store all of your rules. Why?

The complete error is:
There is not enough space on the Microsoft Exchange Server to store all of your rules. The rules that failed to upload have been deactivated.

Exchange 2003 and earlier supports 32KB worth of rules per folder. This cannot be changed. One work around is to create a general rule to move emails to another folder and place more rules on this new folder.

The reason for this 32Kb limit?

The reason for the memory limit is that the total sum of the information that is contained in a user’s rules must fit in a remote procedure call (RPC).

The limit for Exchange 2007 and 2010 by default is 64KB but can be extended to 256KB.

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