In your Exchange 2010 or 2013 Environment, you might have a called logged by a user/s whereby they cannot add in new mailbox rules within outlook or when you are saving a rule you come across the following error:

One or more rules could not be uploaded to Exchange server and have been deactivated. This could be because some of the parameters are not supported or there is insufficient space to store all your rules.

Before we jump into this, take note that this is not a full mailbox error.

The rule size limit for mailboxes in Exchange Server 2010 has a default size of 64 KB per mailbox. This can be increased to a maximum of 256 KB per mailbox.

To perform the increase, you will need to launch the Exchange Management Shell (EMS). Let's first check a users quota, you can run the command below:

  • Get-Mailbox | fl displayname,rulesquota

As you can see above, the user has the default quota of 64kb applied.

To increase the limit you can run the following command:

  • Set-Mailbox -RulesQuota:256kb

Now we can go back and verify the new info by running the same command as we first ran:

  • Get-Mailbox | fl displayname,rulesquota

As you can now see, the user's rules quota has been updated to 256kb, give it a few minutes and then try and save that outlook rule and it should go through.