Even though I have boosted upload capabilities with
php_value memory_limit 40M
php_value max_execution_time 200
php_value max_input_time 200
I still get error that the uploaded file cannot be moved. With WP-Debug I get:
Warning: Cannot modify header information - headers already sent by (output started at /home/domain.com/public_html/wp-content/plugins/all-in-one-seo-pack/all_in_one_seo_pack.php:537) in /home/stichtingdna.nl/public_html/wp-admin/async-upload.php on line 26
You have unexpected whitespace (either a space or an entire line) on line 537 of the /wp-content/plugins/all-in-one-seo-pack/all_in_one_seo_pack.php file. See this guide for more info.
Alternatively, replacing the file with one from a fresh download may resolve the issue.
Thanks for the answer MacManx. Will probably do an upgrade of the plugin firsta and see. Other FTP issue seems to be an upload cap which I am looking into as well.
You're welcome! You might want to contact your hosting provider about the upload cap. It may be hard-coded into the server configuration.
Fixed the issue. Hosting package upgrade and now all is peachy.