Warning and Errors

So... now when I add a new blog or change a blog from non-supporter to supporter I have been getting this message:

Warning: fopen(/home/slpconte/public_html/wp-content/plugins/akismet/akismet.php) [function.fopen]: failed to open stream: No such file or directory in /home/slpconte/public_html/wp-includes/functions.php on line 4165

Warning: fread(): supplied argument is not a valid stream resource in /home/slpconte/public_html/wp-includes/functions.php on line 4168

Warning: fclose(): supplied argument is not a valid stream resource in /home/slpconte/public_html/wp-includes/functions.php on line 4171

Fatal error: Cannot redeclare wpcat2tag_importer_init() (previously declared in /home/slpconte/public_html/wp-content/plugins/wpcat2tag-importer/wpcat2tag-importer.php:495) in /home/slpconte/public_html/wp-content/plugins/wpcat2tag-importer/wpcat2tag-importer.php on line 496