Sounds like virus and you need to go online with a different Browser to find a way to remove it. Otherwise you need to take in to a computer shop to remove it. This request isn't a Firefox problem.

Hello calphil1,

Unfortunaltely you're dealing with a browser hijacker, malware that you of course will want to get rid of.

Go to the Firefox menu (≡) => Add-ons => Extensions and remove anything that looks unfamiliar or suspicious.

Do the same in Windwos Control Panel.

Next step : run malwarescans - further information can be found in this article : https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware?cache=no

Run most or all of the listed malware scanners. They all work differently - what one program doesn't pick up, the other might.

Also see : https://malwaretips.com/blogs/remove-search-hdownloadmyinboxhelper-com/

thank you

thank you