Users may report that they are unable to manually archive or restore any of their email items due to the Enterprise Vault (EV) client extension toolbar missing from their Outlook or OWA application. However, users are still able to retrieve and open their existing archived mail items without any problems and no issues are reported during the scheduled Exchange Archive Task run.

Even though the users are enabled in Enterprise Vault (EV), their client extension toolbar remains missing until the next Exchange Archiving Task has run or when the users initiate a mailbox cleanup to remove unwanted mail items and their mailbox is re-synchronized via the EV Administration Console (VAC) , after which point the EV client extension toolbar re-appears in the application.

This issue does not occur by design; however, it is contributed by the Exchange Mailbox Quotas set on users mailboxes within the Exchange Server and the time line that takes place during a server side mailbox synchronization and the quota being reached. Please refer to the example below for further explanation of this.

Example

If a user goes over their Exchange Mailbox Quota limit, which is set on their mailbox within the Exchange Server, everything will continue to work on the client, until the next time the mailbox synchronizes.

At this point, the hidden message within the users settings is deleted and a new one created. However, Enterprise Vault (EV) is unable to recreate the hidden message, due to the user being over the Exchange Mailbox Quota limit and as such, when the client application opens, it tries to read the hidden message (which is no longer there) and Enterprise Vault (EV) thinks that the user is disabled and the EV client extension toolbar is not shown.

Therefore, the issue is based on a number of factors that will show some users as having the EV client extension toolbar showing, but are unable to restore or archive manually by using them and other users as not showing the EV client extension toolbar at all.

The factors that affect this are the "Exchange Mailbox Quota" setting, the "Hidden Message" being deleted and the "Synchronization" process, that all contribute to this phenomenon.