cdnError while capturing HTTPS coonects from outlook in ubuntu

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Lorraine asked on 19 Mar 2023, 09:20 AM

When I close fiddler, I can access to outlook; while using fiddler, I fail to visit it with the error message below:

UTC Date: isn't important
Client Id: isn't important
Session Id: isn't important
Client Version: 20230310007.15
BootResult: cdnError
Failed resource:
Back Filled Errors: Unhandled Rejection: Error: Failed to load localized strings:undefined|Unhandled Rejection: Error: Failed to load localized strings:undefined|undefined:undefined|undefined:undefined
err: Error: Failed to load localized strings
esrc: InitLoc
et: ClientError
estack: c@'t important
a/a<@'t important
My ubuntu version is 18.04.6 and my fiddler version is v4.6.20171.26113.

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Nick Iliev
Telerik team
answered on 20 Mar 2023, 06:12 AM

Hello Lorraine Xu,


Most Office365 products, including Outlook, are not handling the system proxy's dynamic change very well. That said, the best approach is explicitly bypassing them within Fiddler so that their traffic goes directly upstream.

You can open Fidder Classic > Tools > Options > Connections and bypass the below endpoints in Bypass Fiddler Classic for URLs that start with: field.

*;*; *;*;

You need to replace yourcompany with the domain address used by your organization.  After the change, ensure that your Outlook is fully restarted so that the change can take place.



Nick Iliev
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