Help!! from a wordpress newbie- weird error code

Hi, I am new to wordpress, but have been successfully uploading videos to my wordpress blog for a while now until I got this weird message:

Warning: file(/nfs/c07/h01/mnt/110986/domains/freshwave.ca/html/wp-content/themes/Nova/timthumb.php) [function.file]: failed to open stream: Permission denied in /nfs/c07/h01/mnt/110986/domains/freshwave.ca/html/wp-admin/includes/theme.php on line 187

Warning: implode() [function.implode]: Invalid arguments passed in /nfs/c07/h01/mnt/110986/domains/freshwave.ca/html/wp-admin/includes/theme.php on line 187

Warning: Cannot modify header information – headers already sent by (output started at /nfs/c07/h01/mnt/110986/domains/freshwave.ca/html/wp-admin/includes/theme.php:187) in /nfs/c07/h01/mnt/110986/domains/freshwave.ca/html/wp-includes/pluggable.php on line 934

Does anyone know what this means and what am I doing wrong?
Thanks
Greg