Solution!!! Microsoft Outlook 2010: The set of folders cannot be opened. The attempt to log on to the Microsoft Exchange has failed.

I have a customer who encountered the error message mentioned above while trying to access her group mailbox account via Outlook 2010. Investigation shows that she had accessed/used her group mailbox before it stopped working.

From all indications, the above flagged message is related to permission issues which must be reconfigured to restore my customer's access to her group mailbox account

Solution:

• Launch Microsoft Exchange Server 2010 Management console
• Search for group mailbox acount
•  Right click mailbox account
• Select Manage Send As permission
• Remove customer's "Manage Send As permission" and
• Remove Customer's "Full Access permission"  then
• Re-add customer's account on Manage Send As and Full Access permissions respectively then
• Remove and re-map customer's group mailbox account from Outlook client 2010