Question : What is the Maximum Inbox size on Exchange 2003 running Echange SP2

Running Exchange 2003 with SP2 for Exchange.  Outlook 2003 as the mail email client.

What is the maximum Mailbox size running this verison of Exchange  ona per use mailbox ?

Answer : What is the Maximum Inbox size on Exchange 2003 running Echange SP2

Assuming you have mailbox quotas and size limits disabled on the Exchange Organization, Store and the individual user objects in AD, then there is no maximum size on a per-mailbox basis. The mailbox size is governed by the maximum permitted size of the store.

If you are running Exchange 2003 Standard then this is limited to a maximum of 75GB after applying a registry change: http://www.msexchange.org/tutorials/Explaining-Database-size-limit-changes-Exchange-2003-Service-Pack-2.html. Since you are restricted to one mailbox store in Standard Edition this effectively limits you to a maximum of 75GB of storage overall in all your mailboxes.

For Exchange 2003 Enterprise Edition the mailbox store size limit is the maximum data you can store on an NTFS partition - 16TB if I remember rightly. Of course if you have Enterprise Edition, you are probably a larger company which should be utilising several mailbox stores and/or Exchange Servers to spread load and data across several databases.