Using UploadFile(\"upload.php\", \"POST\", filePath) with WebClient anything over 4mb will not upload. The limit in PHP is set at 48mb. Is there I need to set in C# ?
There is a default maxRequestLength set at 4MB in ASP.NET, you can change it in the web.config.
The length is specified in KB in the config file. If you are using IIS there is an additional limit set at 4MB by IIS.