SSL Authentication Error - Handshake failed due to an unexpected packet format.

2 posts, 0 answers
  1. Im
    Im avatar
    1 posts
    Member since:
    May 2018

    Posted 05 May 2018 Link to this post

    As you can see above, im using C# and its returning a Handshake Error (sslStream.AuthenticateAsClient(host)).

    This is ONLY occuring if I connect via proxy to ipv4:8888 (Fiddler's Proxy).

    If I were to close off fiddler and use another proxy, or no proxy at all, it would work fine.


    Honestly clueless as to why its occuring. My library had 1 other connection issue due to incorrectly syncing a for a statusline check causing fiddler to show a red/yellow icon ( but I sorted that out.


    Now im just trying to figure out why this is occuring.

  2. Alexander
    Alexander avatar
    383 posts

    Posted 16 May 2018 Link to this post


    What cryptographic protocols is the server you are trying to connect to demanding? Also what protocols are enabled in Fiddler - Tools -> Options -> HTTPS -> Protocols?

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