-> Tap ALT key or press F10 to show the Menu Bar

-> go to Help Menu -> select Restart with Add-ons Disabled

Firefox will close then it will open up with just basic Firefox. Now do this:

-> Update ALL your Firefox Plug-ins https://www.mozilla.com/en-US/plugincheck/

-> go to View Menu -> Toolbars -> unselect All Unwanted/Incompatible Toolbars

-> go to Tools Menu -> Clear Recent History -> Time range to clear: select "EVERYTHING" -> click Details (small arrow) button -> place Checkmarks on Cookies, Cache -> click Clear Now

-> go to Tools Menu -> Options -> Content -> place Checkmarks on:

1) Block Pop-up windows 2) Load images automatically 3) Enable JavaScript

-> go to Tools Menu -> Options -> Privacy -> History section -> Firefox will: select "Use Custom Settings for History" -> REMOVE Checkmark from "Permanent Private Browsing mode" -> place CHECKMARKS on:

1) Remember my Browsing History 2) Remember Download History 3) Remember Search History 4) Accept Cookies from sites -> select "Exceptions..." button -> Click "Remove All Sites" at the bottom of "Exception - Cookies" window

  4a) Accept Third-party Cookies -> under "Keep Until" select "They Expire"

-> REMOVE CHECKMARK from CLEAR HISTORY WHEN FIREFOX CLOSES

-> When using the Location Bar, suggest: select "History and Bookmarks"

-> go to Tools Menu -> Options -> Security -> place Checkmarks on:

1) Warn me when sites try to install add-ons 2) Block reported attack sites 3) Block reported web forgeries 4) Remember Passwords for sites

-> go to Tools Menu -> Options -> Advanced -> Network -> Offline Storage (Cache): click Clear Now button

-> Click OK on Options window

-> click the Favicon on SearchBar -> click Manage Search Engines -> select all Unwanted Search Engines and click Remove -> click OK

-> go to Tools Menu -> Add-ons -> Extensions section -> REMOVE All Unwanted/Suspicious/Incompatible Extensions (Add-ons) -> Restart Firefox

-> go to Tools Menu -> Add-ons -> Appearance section -> REMOVE All Unwanted/Suspicious/Incompatible Themes (Persona) -> Restart Firefox

You can enable your Known & Trustworthy Add-ons and Themes later. Check and tell if its working.

hi! thanks for the help but having the same problem and got a new problem as well : i cant access gmail via firefox its looping me back to the access page the username & password are correct

Cookies are blocked

https://support.mozilla.com/en-US/kb/Websites%20say%20cookies%20are%20blocked

Cannot log in to websites

https://support.mozilla.com/en-US/kb/Cannot%20log%20in%20to%20websites

Check and tell if its working.