Overwriting Mailbox Store Policy limits in Exchange 2003
Exchange Server 2000/2003 allows the Exchange Administrator to set limits on the mailboxes of users in the Exchange Organization. Setting limits on the mailboxes help control the database size and plan for efficient backup, restore and maintenance tasks (read Calculating Storage Space in Exchange for more info).
These settings, when applied, will enforce limits on all the mailboxes in that store (or many stores if set by using policies).
Note that in order to set mailbox limits over 3GB you will need to manually edit the information in AD. The UI will not let you specify these sizes. Read Setting Mailbox Limits over 2GB for more info.
However, if you have Mailbox Store settings in place or Mailbox Store Policies up and running and effecting many stores, you might still want to exclude specific users from these limits. The best method of excluding these mailboxes will be by putting them in a separate store, and configure higher limits on that store. However in some scenarios this is not possible (for example - when using Exchange Server 2000/2003 Standard edition or SBS, where only one Mailbox Store is possible).
Therefore we need to overwrite the mailbox limits for specific users. Setting Mailbox limits on the user account properties in Active Directory Users and Computers (ADUC) will overwrite the same settings on the Mailbox Store or Mailbox Store Policies, and are stronger than these settings.
For example, if you have 10 servers with 10 Mailbox Stores each, and you've set up a Mailbox Store Policy that configures a 500 MB mailbox limit on all these stores, all the users that have mailboxes in these stores will have these limits on their mailboxes. However, if your VIP users need more than 500 MB in their mailboxes, you could select these user accounts and manually set their limits to, let's say, 1500 MB. On the other hand, if there are users that need less than the 500 MB limit (temporary users, contract users etc.) then again, you could select these user accounts in ADUC and manually set their limits to, let's say, 50 MB.
Method #1: ADUC - One user at a time
In order to set mailbox limits on one user accounts follow these steps:
Open Active Directory Users and Computers.
Expand your domain tree, find the user account you need to modify.
Right-click the user account, select Properties.
In the Exchange General tab click on the Storage Limits button.
In the Storage Limits window, click to un-select the Use Mailbox Store Defaults checkbox. Then click to select the first of the 3 limits settings, and enter the right limit in KB.
When done click Ok twice.
Repeat these steps for any user you need to modify.
Method #2: ADmodify - Many users at the same time
You can download ADmodify .NET v2.1 from the following link:
ADmodify does not need any installation, just unzip and run it.
ADmodify is a wonderful tool. One of the reasons is because it will allow you to modify almost any user or group attribute, and will do it for as many objects as you need.
Run ADmodify. Click on Modify Attributes.
In the main ADmodify window, select your domain, domain controller, and unselect any objects you do not wish to include in the list (like groups for example). Finally, click on the green arrow.
The domain tree list will populate itself. Expand it and browse to the right OU. You can click Add to List to simply add all the required user, group or Public Folders objects to the right pane, or if needed, you can also create a custom LDAP query (read LDAP Search Samples for Windows Server 2003 and Exchange 2000/2003 for more info), and even traverse containers (In the following screenshot you can see that all user objects are displayed from all of the Help Desk child OUs).
Select all or some of the objects from the right pane and click on Next.
In the editor window click on the Exchange Features tab. Click to select the Storage Limits leftmost checkbox, then click to select any of the 3 attributes checkboxes and enter the required value(s). When done, click Go!
(don't mind the numbers, they are just examples)
All the users accounts that were selected will now be given the mailbox limits you've set.
You might also want to read the following related articles: