For Chrome:
https://support.google.com/chrome/answer/95472?hl=en
For Firefox:
https://support.mozilla.org/en-US/kb/pop-blocker-settings-exceptions-troubleshooting
For Safari:
http://www.geeksquad.com/do-it-yourself/tech-tips/disable-pop-up-blocker.aspx#safari
For Internet Explorer:
http://www.geeksquad.com/do-it-yourself/tech-tips/disable-pop-up-blocker.aspx#ie