Comment on How to Update WordPress Themes by SEO Dave.
The uploaded file exceeds the upload_max_filesize directive in php.ini.
The upload error message above means your hosting account/server has it’s maximum file size set to a smaller size than the Stallion zip file, Stallion is ~9MBs, so below 10MBs basically : many hosts set it really low at 2MBs, why I don’t know, must result in loads of support requests, I wonder if it’s left over from when HD space was at a premium?
Use FTP to upload the unzipped Stallion theme.
Get your host to increase upload_max_filesize to 24MBs or more (24M will give you plenty of wiggle room for other stuff you might upload).
Edit your php.ini file and add or edit
upload_max_filesize = 24M
You might have a php.ini file in the root of your website.
Not tried this but apparently you can add this to your root .htaccess file as well format:
php_value upload_max_filesize 24M
If this .htaccess change results in a 500 Internal server error it apparently means you aren’t allowed to do this on your server.
Easiest solution is FTP.