Usually Firefox's built-in popup blocker won't block a window if you clicked a link or button to open it. It is designed to block windows that open without you taking a specific action.

One possibility is that the link/button is in a part of the page that is "blocked" by an invisible element. Another possibility is that the script that opens the window is not running correctly.

When you have a problem with one particular site, a good "first thing to try" is clearing your Firefox cache and deleting your saved cookies for the site.

(1) Bypass Firefox's Cache

Use Ctrl+Shift+r to reload the page fresh from the server.

Alternately, you also can clear Firefox's cache completely using:

orange Firefox button (or Tools menu) > Options > Advanced

On the Network mini-tab > Cached Web Content : "Clear Now"

If you have a large hard drive, this might take a few minutes.

(2) Remove the site's cookies (save any pending work first). While viewing a page on the site, try either:

• right-click and choose View Page Info > Security > "View Cookies"
• Alt+t (open the classic Tools menu) > Page Info > Security > "View Cookies"

In the dialog that opens, you can remove the site's cookies individually.

Then try reloading the page. Does that help?

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Also make sure that your security software isn't blocking pop-ups.

Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

Still wouldn't work....once again, this is for printing an email from yahoo.mail.....works for IE and Chrome....actually in Firefox for my juno email printing works....meaning my printer dialog box comes up for me to choose copies, pages, etc.....

Also, my work email, which if I normally want to create a new email, that new pop up email template won't work....so frustrating...

For Yahoo:

When you choose Print from the menu, do you get an error message overlaid over the page -- or just nothing happens?

For work email:

Do you use Outlook Web App from an Exchange Server? Gmail? Something else?

Today is my first day on Yahoo's new interface, so I'm not sure I'm seeing it the way you do. I've attached a screen shot of what I have now.

Edit: Deleted duplicate suggestion about Safe Mode

Hello, I have been having a problem using Firefox in my online class. Every time I would click on the homework section little windows would appear and then disappear and the homework page would not open. While troubleshooting this process there was only rarely (once out of every 20 attempts) any feedback about what was going on, that coming from the distant end server warning that apparently I was blocking popups. I don't have any active extensions enabled. I have tried adding every site name associated with mymathlab that I could into the exceptions list. That didn't help either. Then I tried turning off popup blocking all together, no help. Finally I selected override automatic cache management and now no more issues. Now I just have to catch up on my homework. Maybe this will work for you.