Fiddler

Fiddler Unable to Decrypt HTTPS Traffic

I recently ran into an issue with Fiddler where after upgrading I was unable to decrypt HTTPS traffic. I tried resetting the certificates, every single walk through on the Telerik site, I even did a complete uninstall, searched the registry for fiddler, removed all references, located all “DO_NOT_TRUST” fiddler certificates in the Certificate Store and just wiped them out.

Still Nothing. God dammit.

and then after I cooled down I found this answer on a google group. I’m re-posting here to help spread the love.

This certificate was placed here by me of all people. it was a response to the annoying popup generated by officeapps.live.com. you may have seen this popup:
2017-02-16_15-29-44
When you reset all certs this private key was mismatched and caused the problems.

TO FIX THIS ISSUE, DELETE THIS FILE:

>C:\Users\<UserName>\Documents\Fiddler2\ClientCertificate.cer

Immediately after this I was able to decrypt HTTPS pages again.
Google Group Source here