When in a learning session pop-up blockers need to be disabled. There are many pop-up blockers available on the market. If you are using Microsoft XP or VIsta , then your version of Internet Explorer is equipped with a built-in pop-up blocker. Mozilla Firefox, also has built-in pop-up blockers. You may also use a toolbar, such as Google Toolbar or Yahoo Toolbar, with a built-in pop-up blocker.
Internet Explorer

To disable pop-ups in Internet Explorer, go to Tools >>>> Pop-up Blocker >>>> Turn Off Pop-up Blocker.
Firefox or Mozilla on a PC

To disable pop-ups in Firefox, go to Tools >>>> Options. Once the Options window is open, as indicated to the left, click on Web Features. Next, UN-Check the Block Popup Windows Box. Click OK at the bottom to accept the changes.

To disable pop-ups in Mozilla, go to Edit>>>> Preferences. Once the Preferences window is open, as indicated to the left, click on Privacy & Security. Next, click on Popup Windows. Next, UN-Check the Block Unrequested Popup Windows Box. Click OK at the bottom to accept the changes.
Firefox on a Mac
To disable pop-ups in Firefox, go to Firefox >>>> Preferences.... Once the Preferences window is open click on Content.

Next, UN-Check the Block pop-up windows Box. Click OK at the bottom to accept the changes.
Google Toolbar

To disable pop-ups from the Google Toolbar, click on Options Once the Toolbar Options window is open, UN-Check the Popup Blocker Box. Click OK at the bottom to accept the changes.
Yahoo

To disable pop-ups from the Yahoo Toolbar, Click on the small picture of a window with a shield. Click on Enable Pop-Up Blocker to uncheck this option.
Acknowledgement and thanks to the Ohio Library system sites who's tutorial I adapted for moodle users.