Increasing the Upload Limit of my PHP script
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I have a simple PHP script. Its used to upload users into the joomla tables. Basically it uploads users into joomla three main tables. 

The PHP uploader sript works fine when the CSV is about 80MB to 100 MB. 

It does not work or just nothing happens when the file size is 500MB or above.

How do i make the PHP script work to upload the CSV files of over 500 MB?

Do i actually change something in my PHP.ini settings or is there something else i could
add in the script itself.

Thanks in Advance.   