Default ports for Outlook for Mac 2011

Office for Mac 2011 will reach end of support on October 10, 2017. To stay supported, you will need to upgrade. For more information, see these resources.

 

Applies to: Office for Mac 2011

Topic Last Modified: 2015-03-09

Microsoft Outlook for Mac 2011 uses default ports for standard communication protocols. Your network and account configuration may require some or all of the ports that are listed in the following table.

Default port	Used for
80	HTTP Exchange Web Services uses HTTP for functions such as synchronizing mail, public folders, contacts, and events.
443	HTTPS HTTP with Secure Sockets Layer (SSL), if SSL is enabled for Exchange Web Services
53	DNS queries To locate the Active Directory global catalog server for a user account, Outlook sends DNS queries to DNS servers.
1023 (and higher)	DNS query responses
3268	LDAP global catalog searches To obtain Global Address List (GAL) data, Outlook sends LDAP queries to the Active Directory global catalog server.
3269	LDAP global catalog searches with SSL
389	Other LDAP searches and authentication and domain password expiration check
636	Other LDAP searches with SSL and authentication and domain password expiration check
25	SMTP and SMTPS (SSL/TLS) Many ISPs now use port 465 or port 587.
143	IMAP
993	IMAP (SSL)
110	POP
995	POP (SSL)