OWA Error - A problem Occurred While Trying to Use Your Mailbox"

We recently ran across a problem where users trying to log on to Microsoft Office Outlook Web Access in Exchange Server 2007 would receive the following error message:

"A problem occurred while trying to use your mailbox. Please contact technical support for your organization."

According to KB941146, this behavior is caused by an attribute – msExchVersion being 0 for the affected user. To fix this error you need to run the following command from Exchange PowerShell.

1. Get-Mailbox <user name>  | format-list ExchangeVersion

2. If the output is less than 1.0 then you need to run

 Set-Mailbox <user name> –ApplyMandatoryProperties

3. Then go to your Active Directory Users and Computers

4. On the View menu, select Advanced Features

5. Then select the user account who is experiencing the issue and click on Properties

6. Click on the Security tab and select Advanced

7. Make sure you check the box on 'Include inheritable permissions from this object's parent'