issue during upgrading 2.2.4 to 3.0

The error message indicates that a session was started before the session library was loaded. Without code or even the full text of the error messages, I can't really tell you what's going on. I certainly wouldn't put the file name in a query string when I'm sending a POST, but that probably has nothing to do with the session error or the Uploader::$load error for which you can't even see the filename/line number in the screenshot.

If you didn't change the JavaScript going from CI 2.x to 3.0, then the JavaScript probably isn't the problem, unless your configuration changed in some way which is significant to the error at hand.

Bonfire

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