Increasing Email Size Limits for your High Profile Users in Exchange 2010

Usage amount of business happens through the medium of email. E-mail is naturally one of the Business Critical applications in almost every organization. With that in mind, maximizing the performance of your Exchange infrastructure is clearly a priority,
and restricting the average message size which your users can send/receive is a good step in that direction.

Use the EAC to configure storage quotas for a mailbox

In the EAC, navigate to Recipients
> Mailboxes.
In the list of user mailboxes,
click the mailbox that you want to change the storage quotas for,
and then click Edit Edit icon.
On the mailbox properties page,
click Mailbox Usage, and then click More options.
Click Customize the settings for this mailbox,
and then configure the following boxes.
The value range for any of the storage quota settings is from 0 through 2047 gigabytes (GB).
Issue a warning at (GB) This box displays the maximum storage limit before a warning is issued to the user.
If the mailbox size reaches or exceeds the value specified, Exchange sends a warning message to the user.
Important:
The message associated with the Issue warning quota won’t be sent to the user unless the value of this setting is greater than 50% of the value specified in the Prohibit send quota. For example, if you set the Prohibit send quota to 8 MB, you must set the Issue warning quota to at least 4 MB. If you don’t, the Issue warning quota message won’t be sent.
Prohibit send at (GB) This box displays the prohibit send limit for the mailbox. If the mailbox size reaches or exceeds the specified limit, Exchange prevents the user from sending new messages and displays a descriptive error message.
Prohibit send and receive at (GB) This box displays the prohibit send and receive limit for the mailbox. If the mailbox size reaches or exceeds the specified limit, Exchange prevents the mailbox user from sending new messages and won’t deliver any new messages to the mailbox. Any messages sent to the mailbox are returned to the sender with a descriptive error message.
Click Save to save your changes.
Using the Shell to configure storage quotas for a mailbox

This example sets the issue warning, prohibit send, and prohibit send and receive quotas for Joe Healy’s mailbox to 24.5 GB, 24.75 GB, and 25 GB respectively.

Example 1: To ensure that the custom settings for the mailbox are used rather than the mailbox database defaults, you must set the UseDatabaseQuotaDefaults parameter to $false.

c:/>Set-Mailbox -Identity “Joe Healy” -IssueWarningQuota 24.5gb -ProhibitSendQuota 24.75gb -ProhibitSendReceiveQuota 25gb -UseDatabaseQuotaDefaults $false

Example 2: This example sets the issue warning, prohibit send, and prohibit send and receive quotas for Ayla Kol’s mailbox to 900 megabytes (MB), 950 MB, and 1 GB respectively, and configures the mailbox to use custom settings.
Set-Mailbox -Identity “Ayla Kol” -IssueWarningQuota 900mb -ProhibitSendQuota 950mb -ProhibitSendReceiveQuota 1gb -UseDatabaseQuotaDefaults $false

How do you know this worked?

To verify that you’ve successfully set the storage quotas for a mailbox, do one of the following:

Example 1: In the EAC,
Navigate to Recipients > Mailboxes.
In the list of user mailboxes, click the mailbox that you want to verify the storage quotas for, and then click Edit Edit icon.
On the mailbox properties page, click Mailbox Usage, and then click More options.
Verify that Customize the settings for this mailbox is selected.
Verify the storage quota settings.

Example 2: Run the following command in the Shell.
c:/>Get-Mailbox <identity> | fl IssueWarningQuota,ProhibitSendQuota,ProhibitSendReceiveQuota,UseDatabaseQuotaDefaults