Start Outlook with a profile that is configured for the Exchange Server mailbox for account B. You may have to log on to the network as the user of account B for proper validation.
On the Tools menu, click Options.
On the Delegates tab, click Add.
Type or select the name for the user of account A, click Add, and then click OK.
In all lists, click to select Editor (can read, create, and modify items) in the Delegate Permissions dialog box.
Click OK two times.
If the Folder list is not visible, click Folder List on the View menu.
Right-click Mailbox – user name, and then click Properties for ‘Mailbox – user name on the shortcut menu.
On the Permissions tab, click Add.
Type or select the name for the user of account A, click Add, and then click OK.
In the Name box, click the newly added entry for account A.
In the Permission Level box, click Owner, and then click OK.
Repeat steps 8 through 12 for all the other folders in the mailbox.
On the File menu, click Exit and Log Off.
Restart Windows, and then log on as the user of account A.
Start Outlook with a profile that is configured for the Exchange Server mailbox for account A.
On the Tools menu, click Account Settings.
On the E-mail tab, click the name of the account, and then click the Change icon.
Click the More Settings button.
Click the Advanced tab.
Click Add to add an account to the Open these additional mailboxes: list.
Type the name for the user of account B, and then click OK three times.
Click Next, click Finish, and then click Close.

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