WARNING and Errors! on upload

Hi All,

I have recently moved my installation from local to live server and are now getting 2 errors that I cant seem to understand. All help is GREATLY appreciate it. I am panicking!

here are the errors:

Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, ‘gallery_slider’ was given in /home/daviles1/public_html/avidsg.com/wp-includes/plugin.php on line 405

Warning: Cannot modify header information – headers already sent by (output started at /home/daviles1/public_html/avidsg.com/wp-includes/plugin.php:405) in /home/daviles1/public_html/avidsg.com/wp-includes/pluggable.php on line 934