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MITM certificate uses SHA1 - Now considered deprecated by Chrome

As of recently, Chrome started to alert about sites that have SHA1 SSL certificates (and if they have HSTS, blocks them completely). Because Fiddler's self-signing certs use SHA1, that makes it problematic to use fiddler with chrome.
  • Guest
  • Apr 9 2017
  • Under review
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  • Eric Lawrence commented
    10 Apr, 2017 06:43pm

    Fiddler, in general, does not use SHA1 in its certificates unless you haven't updated it in many years, or you've set an obscure preference. 

    On what platform are you having a problem? Which certificate maker are you using (see the blue link in Tools > Fiddler Options > HTTPS).

    See for background. Using the "Reset Fiddler certificates" button in the Action button is probably enough to fix you up.