Anybody who was having trouble with 2.7.6, try 220.127.116.11
If it is not working for you, you must test for a plugin conflict.
Here is how to troubleshoot which plugin is conflicting:
Look on the Admin – Plugins – menu.
Temporarily deactivate (not uninstall) all your other plugins. Leave this one still activated.
Does it work now? If yes, Activate the other plugins one by one to determine which one conflicts. Which one was it?
If you still have trouble I need to know:
What is the error or problem?
What steps to reproduce the problem?
Which form is it doing that on? login, comment, registration, or lostpassword
What version of WordPress?
Do you have multi-site or BuddyPress installed?
Are any other plugins causing it? (deactivate all the others to see if the problem goes away)
Yes you can go back to a previous version:
FTP to the server and delete this folder: /si-captcha-for-wordpress/
the folder is found in /wp-content/plugins/
Unzip the file on your computer.
Use a FTP program such as FileZilla to connect to your web server .
FTP File Transfer this folder this folder: /si-captcha-for-wordpress/ from your downloaded files to the folder on your server: /wp-content/plugins/
On the plugins admin page, find SI CAPTCHA and click “Activate”. The plugin will now be activated.