hello musicport, you have various malicious addons present. so please perform all these steps:

1. reset firefox (this will keep your bookmarks and passwords)
2. afterwards go to the firefox menu ≡ > addons > extensions and in case there are still extensions listed there, disable them.
3. finally run a full scan of your system with different security tools like the free version of malwarebytes and adwcleaner to make sure that adware isn't present in other places of your system as well.

Troubleshoot Firefox issues caused by malware

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. Remove Yahoo Anything. Now do the same in the computers Programs Folder.

Windows: Start > Control Panel > Uninstall Programs. Mac: Open the "Applications" folder. Linux: Check your user manual.

After the problem is fixed, Bookmark and use this; Download the Mozilla Search Reset {web link} This add-on is very simple: on installation, it backs up and then resets your search preferences and home page to their default values, and then uninstalls itself. This affects the search bar, URL bar searches, and the home page.

I've done all that then all seemed fine until Mozilla crashed - when it re-opened it was all Yahoo again - there are no add-ons listed now so I cant get rid that way

Hi, something must have been missed when you ran the anti-malware programs, so try working through How to remove Searchinterneat-a.akamaihd.net (Guide) by Malware Tips.

Note that not all removal programs will detect all malware, so you may need to run all of them.

After removal you may need to reset your home page and search, which you can do by running the add-on SearchReset.

If your question is resolved by this or another answer, please take a minute to let us know. Thank you.

I ran all those and it still reverts back to that address ... Malware blocker wouldn't open it but it wouldn't open this page either or mozilla homepage

musicport said

. . . . all seemed fine until Mozilla crashed . . .

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.