Recently updated to 2.7.7.3 and started getting the same error
ERROR: Unreadable CAPTCHA token file
Changed the permissions on
/wp-content/plugins/si-captcha-for-wordpress/captcha to 777
and it fixed it.
Looks like upgrading the plugin changes the pernmission on that folder back to 755? need to remember to change it to 777 again whenever the plugin is updated, or is this something that Mike can fix?
BTW – thanks Mike for the plugin!
Keith