Remove an "AutoMapped" Mailbox from Outlook 2010

My Outlook takes forever to open.  I've finally figured out why:  I have added too many shared mailboxes that Outlook has to open.  Only I don't remember adding them.  Time to to remove them.  I right-hand click on the shared calendar and "remove calendar."  Outlook throws this error message: ("The group of folders is associated with an e-mail account.  To remove the account, click the File Tab, and then the Info tab, click Account Settings.  Select the e-mail account and then click Remove.)

If the solution were only that easy.  This is a shared mailbox that I have FULLACCESS to;  there is NO EMAIL account in my profile. 

The contributor: (or "feature") is "automapping!! (Here is how to set automapping.)  The solution, for EXCHANGE 2010 Sp2, is to DISABLE AUTOMAPPING!  Here are the powershell commands taken from a Micosoft Technet forum:

Disable automapping between "shared mailbox" and "delegate":
Add-MailboxPermission "Shared Mailbox" -User -AccessRights FullAccess -AutoMapping:$false
  
If you want to set it on all the mailboxes:
$mailbox = Get-Mailbox
$test = $mailbox |
     Foreach {Add-mailboxPermission $_.Name –User ‘administrator’ –AccessRight FullAccess –Automapping $false}

That's it!
Russ