Hi Jason, thank you for your reply. I have done as suggested, delete and reinstall a fresh s2members and s2members-pro.
There were new errors after the reinstall:
[Mon Feb 11 20:01:58 2013] [error] [client 217.160.167.63] client denied by server configuration: /home/asians7/public_html/wp-content/plugins/s2member/includes/timthumb
[Mon Feb 11 20:01:52 2013] [error] [client 217.160.167.63] client denied by server configuration: /home/asians7/public_html/wp-content/plugins/s2member/includes/functions/timthumb.php
These were the most common two error messages.
Any advice is greatly appreciated!
Best,
JC