1. What is the exact error message related to “do you want to view secure or unsecure” error?
2. Have you made any changes on the computer prior to this issue?
3. When exactly do you get this error message?
If you are getting “the script you are running is slowing windows and may make application to not respond” error while using internet explorer then the following article might be helpful.
Error message: “A script on this page is causing Internet Explorer to run slowly”