1. Open an Internet Explorer page -> Go to Tools -> Internet Options -> Go to the Content Tab -> Click on CLEAR SSL STATE.
2. Now go to Start -> Run -> type CMD and press Enter -> type "ipconfig /release" without the "" and press Enter -> type "ipconfig /renew" without the "" and Enter again. (for this second step, you can also click Repair on the Internet connection, it's basically the same thing)

If the error persists, please make sure of the following :

1) Install and update to the latest Internet Explorer for your Windows.
2) Install and update to the latest Adobe Flash Player
3) Install and update to the latest Java Runtime Environment
4) Make sure Internet Explorer is not set to block pop-ups from http://www.cabalonline.com and https://www.cabalonline.com . Make sure these 2 websites are added to the list of trusted sites.
5) Make sure the Internet Service Provider has not installed a transparent proxy on your connection.
6) Update your Cabal following these steps : http://support.cabalonline.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=77&nav=0 (sometimes corrupt files make this issue appear)