What's your computer system and Firefox version?

What are you using as your Homepage?

Some problems occur when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

• Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
• Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet. {web link}

Hi Fred...

I tried the solutions or options provided in the community including firewalls option but neither worked..

I am using Windows 7 Ultimate 32 bit...

my Firefox is running on v 55.0.3 (32 bit) and it is updated one...

You didn't say what you tried, so . . .

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

Start your Computer in safe mode. Then start Firefox. Try Safe websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

finally it worked...

I checked for windows updates...updated suggested service pack and deleted firefox and reinstalled it...still no luck after this...

but I checked somewhere it is showing as it is for Windows some other version but actually it should be windows 7...so i changed that immediately firefox opened normally and working perfectly...

now i dont remember exactly where i changed that option... :(

anyways thanks for helping me Fred...

well i dont see my add-ons now...

I think i selected to restart firefox with disabling/deleting add-ons...

not many just 5...i dont remember all of them...i have to work on my memory now

Have you tried a normal startup?

Yes it is working in normal startup itself but add-ons deleted it seems...

for now everything looks working properly...

thanks

Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control> (Mac=<Command>) <Shift> A)

In the Add-ons Manager, on the left, select Extensions.

Are the add-ons listed?

latest update is it is starting up normally but after 15 or 20 minutes it is crashing...after that close button also not responding, have to use task manager to close the firefox....

i don't know reason...i am fed of this trying to use other browser as my primary preferred

Note: v55 has been giving users problems. Reinstall v54.

https://support.mozilla.org/en-US/kb/install-older-version-of-firefox?cache=no Be sure to read everything here.

If you still want to downgrade, look under; I still want to downgrade. Click the Directory of other versions and languages link. Look for the directory of the version that you want. But, remember that old versions may have security issues.

You should also check out Firefox; Extended Support Release {web link} ESR Notes System Requirements

I downgraded to v54...now again it stuck in middle of video...

i don't know what is the reason...

I called for more help.