Based on the exception message I've found this information
on MSDN. It seems it is not issue of Fiddler, but rather machine configuration.
As a workaround you can export the Fiddler root certificate to the desktop and trust it manually. In order to do so, please, follow there steps:
1. Open Fiddler, go to Tools -> Options -> HTTPS -> Actions -> Export Root Certificate to Desktop
2. Double click the certificate
3. Select if you want to install the certificate in the user store or the machine one
4. Select "Place all certificates in the following store"
5. Click on "Browse..." and select "Trusted Root Certification Authorities"
6. Click Next and Finish
7. New dialog with "The import was successful" message should appear
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