Fiddler, OffCAT, and CODD overview for the O365 Dedicated/ITAR environment


This article describes the following Customer Diagnostic Tools in Microsoft Office 365 Dedicated/ITAR:

  • Fiddler trace
  • Microsoft Customer On Demand Diagnostics Tool (CODD)
  • Microsoft Office Configuration Analyzer Tool (OffCAT)

More Information

Fiddler trace

For reproducing issues that are related to Autodiscover, Outlook Web Access, Exchange Control Panel, and Exchange Web Services

A Fiddler trace may be requested by Microsoft for issues that are related to Outlook Web Access (OWA), Exchange Control Panel (ECP), and Exchange Web Service (EWS). In some cases, a trace may be requested for a Remote PowerShell. 

To run a Fiddler trace, follow these steps:

  • A Microsoft support engineer starts a Support Diagnostics Package to automate the temporary installation of Fiddler, the collection of HTTP traffic during issue reproduction, and file uploads for the support engineers. 
  • Follow the instructions that are provided in 3056890 How to run a Fiddler Trace by using Microsoft Automated Troubleshooting Services .
  • This type of data capture will contain sensitive information such as credentials. Therefore, it's important to carefully follow the steps for password protecting the files and sharing this password with Microsoft. Never send the password through an email message.

    A screenshot of the provide a password page
  • If you experience issues during the process, see 929779 How to help the support team collect FiddlerCap traces  to manually run the Fiddler trace. Before you send the file through an email message, password protect the file. Telephone Microsoft to relay the password (do not send it by email). Or contact Microsoft to set up a secure temporary workspace to upload the file. 
  • If you are reproducing the issue in Remote PowerShell, see 3090768 InvalidShellID error in RPS in Office 365 Dedicated/ITAR  for instructions to start the session so that the trace can capture HTTP traffic.

Microsoft Customer On Demand Diagnostics Tool (CODD)

For troubleshooting issues related to Outlook and OWA connectivity and mail transport (SMTP)

The Customer On Demand Diagnostics (CODD) tool is a Windows-based client application that you can use to address access issues that members of your organization may experience when you try to use Office 365 Dedicated services. It tests the following issues:

  • Client connectivity to Domain Name System (DNS) systems
  • The ability of a client to access the Internet
  • The ability of a client to communicate with Exchange Online Dedicated Client Access servers (CAS)
The output can be used to troubleshoot such problems as the following:

  • Outlook Web App (OWA) main page does not load 
  • Inability to interact with the CAS that provides OWA access 
  • Mail transport (SMTP-related) issues  
  • Outlook client connectivity failures
For more information about these situations, see 2451127 Network diagnostics for the O365 Dedicated/ITAR environment and Customer on Demand Diagnostics User guide.

To download the CODD tool, go to

Microsoft Office Configuration Analyzer Tool (OffCAT)

For troubleshooting Exchange mailbox and Outlook client related configuration issues

The Microsoft Office Configuration Analyzer Tool (OffCAT) provides a detailed report of your installed Office programs. It highlights known problems that are found when OffCAT scans your computer. For any problems that are listed in the report, you are provided a link to a related public-facing article (typically in the Microsoft Knowledge Base) that describes possible fixes. Users can use the tool and download the report. The report can be opened and reviewed remotely or shared with Microsoft. 

This tool is especially useful for finding the following information:

  • Calendaring and delegate scenarios
  • Outlook version details
  • User profile configuration
For more information about OffCAT, see 2812744 Office Configuration Analyzer Tool (OffCAT) information .

To download the OffCAT tool, go to

The following screen shot shows an example of the OffCAT program window. 

A screenshot of the OffCAT page

ID do Artigo: 3133248 - Última Revisão: 08/01/2016 - Revisão: 1