Please provide a screenshot of that message.

https://support.mozilla.org/en-US/kb/how-do-i-create-screenshot-my-problem

It is best to use a compressed image type like PNG or JPG to save the screenshot and make sure that you do not exceed a maximum file size of 1 MB.

Then use the Browse .... button below the Post a Reply text box to upload the screenshot.

i tried to update adobe since it is old it has now been blocked. i was going to uninstall and download the latest but i am unable to download. this is the screenshot from today. i am able to download. i can't complete the final process. please help. thank you!

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

I have a feeling It is the Browsing Protection addon you have so try Firefox Safe Mode to see if the problem goes away. Safe Mode is a troubleshooting mode, which disables most add-ons.

(If you're not using it, switch to the Default theme.)

• You can open Firefox 4.0+ in Safe Mode by holding the Shift key when you open the Firefox desktop or Start menu shortcut.
• Or open the Help menu and click on the Restart with Add-ons Disabled... menu item while Firefox is running.

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article for that.

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help other users who have the same problem.

Thank you.

ok, i accessed safe mode from help menu, i went to history-mozilla, plugin check & updates to adobe download it did the same thing only just a slight faster for the cert. auth. failed box to appear. i am just at a loss.

did you try windows safemode as cor-el said?

I had same problem. My issue was that when using firefox I didn't get a chance to "run" the installer program, only the option to "save" it to downloads. Saving it and then running it does not work. My work around was to use Internet Explorer (sorry) and then choose "Run" and not "save". The downloader will take a couple minutes, but the entire installation program will then be downloaded and installed automatically.