Problem with outlook 2007

Question

i have problem in outlook 2007 , i cannot sending external emails through exchange 2010 sp1
but i can send from owa and outlook 2010  good to extenal and internal i use autodicovry
i dont see any error on outlook or event viewe or view quee nothing
and massge not distintions external emai

Answer 1

Please try to enable RPC encryption on Outllook 2007 and see If it works.
Outlook 2007
To manually update an existing Outlook 2007 profile so that it uses RPC encryption with Exchange 2010, follow these steps:
In Control Panel, open the Mail item.
Click Show Profiles.
Select your profile, and then click Properties.
Click E-mail Accounts.
Select the Microsoft Exchange Server account, and then click Change.
In the dialog box that contains your mailbox server and user name, click More Settings.
In the Microsoft Exchange dialog box, click the Security tab.
Click to select the Encrypt data between Microsoft Office Outlook and Microsoft Exchange check box, and then clickOK (The
screen shot for this step is listed below).
https://support.microsoft.com/kb/2006508?wa=wsignin1.0
Exchange Blog:
www.ntweekly.com
MCSA, MCSE, MCITP:SA, MCITP:EA, MCITP:Enterprise Messaging Administrator 2010,MCTS:Virtualization