PHP and "OpenID authentication failed: Bad signature". If you’re seeing a “Bad signature” error in your PHP OpenID application it could be down to a miscompiled GMP library.
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PHP and "OpenID authentication failed: Bad signature". If you’re seeing a “Bad signature” error in your PHP OpenID application it could be down to a miscompiled GMP library.
I don't have the GMP library, so it defaults to BCMath. However on both WordPress and phpBB implementations I got the bad signature error. In both cases from MyOpenID accounts and the solution was to remove the record for this server from th xxx_openid_associations table...