I am having the same problem. We changed servers about a month ago and now I am getting this error:
This contact form contains CAPTCHA fields, but the temporary folder for the files (E:\websites\aq2\Agencies\public\webroot/wp-content/uploads/wpcf7_captcha) does not exist or is not writable. You can create the folder or change its permission manually.
How/where do I change the "(E:\websites\aq2\Agencies\public\webroot" to the new file location?
@rossgarvey are you getting the same error message?