PHP File Upload- Too Big?

[MrFish]

I've got a file upload form that allows you to upload PDF files. The form contains 2 hidden fields- one is a table and one is an id for the row I'm updating. The form works fine and everything goes smoothly until I got to around 8-9MB PDFs- at which point not only does the file not upload but no fields are posted. I figured this would be an issue with the upload_max_filesize and more likely the post_max_size since it's more than just the file not coming through. When I went to make a change in the htaccess here is what I found-

php_value post_max_size 100Mphp_value upload_max_filesize 15M

The posted form does not exceed either of these limits and even put upload_max_filesize at 100M to be safe. Still- if the file is too big it will not post even the hidden fields. I'm pretty stumped- any ideas on troubleshooting this?

[niche]

Also check your memory_limit in your ini.

[MrFish]

Also check your memory_limit in your ini.

No luck.

[justsomeguy]

It sounds like an issue with post_max_size. If that gets exceeded then PHP receives no form information. Put together a phpinfo page to run there so that you can see what the actual values are that PHP is using, or use ini_get to check those.