[Plugin: Contact Form 7] Emails not coming through, and error message at WP

I have installed Contact Form 7 on a new WordPress install (which I have used many times before “out of the box” with no problems) and for some reason it is not working. It appears to function correctly from the site: I enter my info, hit submit and get a success message. But the email never goes through.

The only clue I have is this: when I try to make any changes to the settings and hit “Save”, I get the following error message:

Warning: array_count_values() [function.array-count-values]: The argument should be an array in /home/wqft/public_html/wp-content/plugins/wordsocial/wordsocial.php on line 175

Warning: in_array() [function.in-array]: Wrong datatype for second argument in /home/wqft/public_html/wp-content/themes/headway/library/api/api-write-panel.php on line 159

Warning: Cannot modify header information – headers already sent by (output started at /home/wqft/public_html/wp-content/plugins/wordsocial/wordsocial.php:175) in /home/wqft/public_html/wp-includes/pluggable.php on line 866

Any help is much appreciated!!