How do you know popups are being blocked -- is the page telling you this, or an infobar?

Is there a particular page where you see this problem? If so, could you post the URL and describe the steps that are supposed to generate the popup?

The page doesn't load and there is a Mozilla bar that shows up at the top of the page stating that the pop-up is being blocked. I then have to click on the "allow" before the page will load. It happens on every link I try to view. The link will attempt to open in a new tab but is always blocked by Mozilla.

It happens no matter what the link - when I am trying to access online training or I need to open a link to forms that have been sent to me. Thanks for the assistance!

Could you click the Exceptions button to the right of "Block pop-up windows" and make sure none of those sites is specifically blocked?

If you have unchecked the box and there is no site-specific setting, that usually does it...

Is it possible that an add-on is doing the blocking? A standard diagnostic to bypass interference by extensions (and some custom settings) is to try Firefox's Safe Mode.

First, I recommend backing up your Firefox settings in case something goes wrong. See Back up and restore information in Firefox profiles. (You can copy your entire Firefox profile folder somewhere outside of the Mozilla folder.)

Next, restart Firefox in Firefox's Safe Mode (Diagnose Firefox issues using Troubleshoot Mode) using

Help > Restart with Add-ons Disabled

In the dialog, click "Start in Safe Mode."

Check the Options dialog > Content to make sure the pop-up blocker is turned off.

If popups now work correctly, this points to one of your extensions as the most likely culprit. If you restart in normal mode, you can try disabling (or adjusting the options of) any that seem possibly popup-related (e.g., security related) here:

orange Firefox button or classic Tools menu > Add-ons > Extensions category

Any change?