It happens to me when I enable ‘version 2’ captcha. I always get “Error: You have entered an incorrect CAPTCHA value. Click the BACK button on your browser, and try again.” I tried it on two different web sites and I don’t have any custom login forms or anything else. Can you check if ‘version 2’ is working with you guys? Thanks.
I had the same problem 5 minutes ago. I couldn’t add any new pages. I disabled all plugins and enabled it again. Then it worked for a while and then appeared it again. What I did was to refresh that error page few times and then problem disappeared.
On my installation, jetpack was the issue. I had to remove it by hand. rm -rm jetpack. Thanks.
How did you solve this? I have the same problem after update.
