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"Unable to complete secure transaction" error

  • The following link has been turning up an "Unable to complete secure transaction" error intermittently the past week with Opera 12.17/Win 8.1x64: It's a private message system so connecting to the message isn't important, but the fact that it returns this error message is. A couple of weeks ago, I had to reset some of my Opera files, including the certificates, and I've had to recertify many. I'm wondering if that's causing this link's problem. If so, what would I do? The link works with other browsers, including O26b. Thanks,

  • After years of using old Opera 11 and 12 i ran in such problems, too. I could not visit some IT security websites and some other anymore.

    Yes, Opera 12 gets many problems with SSL connections on special secured servers. That may be related to certificate problems, unreachable OCSP servers for certificate validation check, or some strange server configuration with Cloudflare servers, or some security fixes with TLS. I had no time to investigate.

    Hint: Did you try to enable TLS v1.1 and TLS v1.2 in Security settings of Opera?
    See Alt P -> Advanced -> Security -> Security Protocols...

    Sorry to say, and sad, but i upgraded to Opera 26 to get rid of these problems. Opera 12 does not get bug fixing any more.

  • I think a number of the certificates included with Opera 12.x must have expired by now ...

  • Thanks. Enabling TLS 1.1 and 1.2 causes random crashes with Opera 12. There's a discussion about this and the OCSP servers issue at the Opera security blog, in the comments section for the 025 post: