[TYPO3] problems with uploads to fileadmin

[Axel]

Hello List!

I'd like to make it possible to upload files to a fileadmin folder with
a size of about 20 MB. For this I have
increased the upload limit in php.ini. But the problem is: When I upload
a file with 10 MB (a .mov)
it uploads and then the process simply stops. No error message, no files
list is shown and the file is simply
not there.

Did I forget some settings or what might be the problem?
Thanks for any hints.

Greets

Axel