Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

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

Select Extensions, locate the add-on. From here you can disable or remove it. Plugins, however, can only be set to Never or Ask. To remove it, you have to remove its program.

Unfortunately file advisor is not shown in the extensions or plug in list it is hdden somewhere

Meaby, you can download over the internet the adware cleaner software, run it once, and than you will reload the operating system, i mean your computer shall shutdown and than re running, open the administrator session , and you should have a note that will appear on your desktop , read it and say me what the software has found on your hard disk.