I have has issues with the image uploader in the past so, I added
<IfModule mod_security.c>
<Files async-upload.php>
SecFilterEngine Off
SecFilterScanPOST Off
</Files>
</IfModule>
to my .htaccess. Now, for some reason, that code is disappearing from my .htacess file. What could be causing my .htaccess to be overwritten with the original code which did not contain the fix above? This is quite puzzling.