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I can't upload files over 250MB in firefox

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I am trying to upload large video files via ajax POST method. I am using Firefox 38.0.5, on Windows 8.1. Upload works fine with files just under 250MB, but it simply gets stuck with larger files. Larger than 250MB file uploads work fine for me in Chrome, Opera and IE. So it can't be the router issue as mentioned here: https://support.mozilla.org/en-US/questions/1059428#question-reply I would be grateful for any insights and suggestions how to solve this. Ty, B.

I am trying to upload large video files via ajax POST method. I am using Firefox 38.0.5, on Windows 8.1. Upload works fine with files just under 250MB, but it simply gets stuck with larger files. Larger than 250MB file uploads work fine for me in Chrome, Opera and IE. So it can't be the router issue as mentioned here: https://support.mozilla.org/en-US/questions/1059428#question-reply I would be grateful for any insights and suggestions how to solve this. Ty, B.

All Replies (3)

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Hey Ty, bokifirefox There are some interesting things with uploads, sometimes I would assume that there is just a limit in the chunks of the file uploaded at a time. However sometimes specific sites have limits as well. And some sites use different methods.

In the past Firefox has a bug that is now fixed uploading large files so this may be difficult to troubleshoot. I would image, since there is not a client/Firefox upload limit, its the website/router etc. Ask your isp as well.

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Thanks. I forgot to mention my tests were done locally (on XAMPP server). File transfers were therefore from one disk to another (or on the same), and take just several seconds or so. So it can't be the router or internet service provider. And >250MB file upload works ok in other browsers, so I am guessing the issue is specific to Firefox. I will see how it behaves in uploads to the real server. But at the moment, I have issue with uploading large files (>50-100MB) on the real server (troubleshooting now) in ALL browsers. Something in the chain: Browser-->Ajax-->Router-->ISP-->PHP settings(php.ini, .htaccess)-->Server is wrong or has limits set.

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Not sure whether the following is relevant, as the issue is several months old now:

Firefox 36 changed something that has an issue in this scenario: you are posting over HTTPS and the destination uses a CISCO ACE load balancer. See: