A Joomla extension upload failed with the error
There was an error uploading this file to the server
Often this error relates to the file size limit configured for the website.
4M is a good starting upload size limit. Although, you may find that 8M is a better value.
The upload file limit is configure in the file php.ini, to be found in the root of the website. When you FTP to your website you may find that the files for the site are located in public_html.
Add the following code to the php.ini and try uploading your Joomla extension again. If the error persists try increasing the value to 8M.
php_value upload_max_filesize 4M
