Exchange-Genie

How to set message size limits in Exchange 2007

Often I see users ask how to set message size limits in Exchange 2007, this can be broken down into 2 areas 1. OWA Attachment Limits and 2. Everything Else This article will not focus on OWA and just configure users message size limits.

Lets start with attachment limits for our Outlook users:

We can set message size limits in 5 places:

1. Global
2. Send connectors
3. Recieve Connectors
4. User level
5. Transport rules

Global Settings:
In the RTM version of Exchange 2007 global setting can only be configured by powershell and by default are set to unlimited. However in Exchange 2007 SP1 you can use EMC to configure this setting.

Open EMS –> Get-Transportconfig

The above command lets us see our global settings

**In an environment when Exchange 2007 is added to an existing Exchange 2003 organization and the global limits are set to unlimited in Exchange 2003 the following attributes are edited in AD (delivContLength ,submissionContLength,msExchRecipLimit) and will be seen with the Get-transportconfig comandlet. **

http://technet.microsoft.com/en-us/library/bb310771.aspx

We use the Set-transportconfig -maxmessagesize 30MB to set our global limits to 30MB

Now if we run our get-transportconfig we can see our maxsend/receive is set to 30MB

Exchange 2007 SP1 has added a this back to the gui (EMC)

2. Send Connectors

From EMS we can use the get-sendconnector commad to show us our max message size for all or our send connectors

If we have a number of send connectors we can perform a get-sendconnector set-sendconnetor -maxmessagesize 30mb now we can validate our configuration with a get-sendco n ne ct or

We can also set this with EMC

3. Receive Connectors
We can use the get-receiveconnector commadlet to show our maxmessagesize for our connectors

To set more than one connector at a type we can use the get-receiveconnector set-receieveconnector -maxmessagesize

Lets use EMC to validate our configuration chan ge. 4. User From EMC we use our get-mailbox comandlet to see our users maxsend and receive size (by default unlimited)

Now we can use set-mailbox -maxsendsize 30mb -maxreceivesize 30mb

Lets use EMC to validate our users settings
5. Transport rules
We can create transport rules from EMS or EMC however I am just going to focus on EMC at the moment.

Open-Emc-Organizational Config- Hub Select the transport rule tab to view your current rules (by default there are none)
Right click or select the action pane New-TransportRule

The first screen ask is to give our rule a name and add a description

Next I am going to set the Condition of “From People” and “When the size of the attachment is greater than or equal to 25000kb”

The next menu ask for an Action item, I have choosen to “Send a bounce message to the Sender with enhanced status code” and I set the message to Jodie is not allowed to send messages over 25mb

Next we see the Exceptions menu, here I am allowing Jodie to send larger attachments to me
by selecting “Except when message is to People” then specify my mailbox

We now have our configuration summary menu

The completion page which shows our powershell command