Outlook logging file lists all the accepted and internal relay domains in the Exchange Server 2010 organization when you enable troubleshooting logging

Consider the following scenario:

• You select the Enable troubleshooting logging (requires restarting Outlook) check box in the Advanced settings of Microsoft Outlook 2010 in a Microsoft Exchange Server 2010 organization.
• You create or reply to an email message in Outlook 2010. An Exchange Web Services (EWS) request is sent to the Exchange server to retrieve the MailTips settings.

In this scenario, the logging file in the Outlook logging folder lists all the accepted and internal relay domains in the organization. If the organization has many accepted and internal relay domains, the logging file becomes large.

Note By default, the logging file is located in the following folder: