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  • Hello,

    I have been trying to access my gmail account with Opera, and Google keeps returning a "Cookie Mismatch" error message, saying they have "detected a problem with your cookie settings". My browser privacy is set to "allow local data to be set" and I have already added '' to the list of HTML exception sites. I would try to email Google, however I currently don't have access to my account any idea what could be causing the mismatch?


  • Have you allowed other google sites? I don't use Gmail myself, but you'd need cookies for the actual mail site at least. Maybe use * and the Gmail site…

  • Surprisingly, private window shows gmail smoothly. Is it opera's problem or gmail's?

  • I've run into this issue before (for me it was caused by importing cookies from another browser into Opera).

    Going to Preferences | Privacy and Security | Cookies | Click 'All cookies and site data' and delete any google/gmail cookies should sort it out.

    Once you've deleted any google cookies, logging into gmail should create a new one that works properly.

  • I have cleared all cookies and deleted all cached information in the browser but the problem persist. Ugh, this is frustrating. I'm thinking on moving back to firefox, at least I never had that issue when trying to access gmail. 😕

  • I have the same issue -
    I deleted all google cookies and my browsing history.
    (google sites worked well in my opera for mac browser until last week)
    I can now access any google sites. Instead I get the mistmatched cookies error message.

  • I had to delete my saved passwords for my google account to solve this problem for myself.