Firefox scam
 

Self and SWMBO use two separate desktops, both W7 64bit. Were both using Firefox as browser. A couple of days ago SWMBO's attempt to log in to FF produced total red screen with message to " 'phone an 0800 number as there had been an attempt to obtain bank details" or some such tosh. Nothing similar on mine. SWMBO can log on via IE with no problem. We use the same router. Malwarebytes doesn't pick up anything , nor does Avast. Have tried uninstalling FF and re-installing but similar result. Does anyone have any helpful advice, please?
TIA

Unusual for Malwarebytes not to catch those. (Pups or BHOs) Not usually dangerous unless you ring the number though. Would uninstall all plugins in Firefox, and this link gives some good hints (not same issue but similar) https://www.pcrisk.com/removal-guide...cal-error-scam

Use IE? :) Sorry, couldn't resist.

The fact that it persists following a r/r suggests something has corrupted the profile.

malwaretips.com/blogs/reset-firefox-settings/

(new posting rule won't let me include the h t t p s : / /)

I'm not sure I understand this.

I get similar messages while browsing directed at my browser (Chrome). I had interpreted this as nothing more than a dodgy site that recognizes my browser and sends a spam warning message to call a number.

Andy and CaptO - thank you both. Swmbo IS now using IE (with great reluctance) Andy - It may be a bit ungracious of me, but it appears that your reference will tell me what I know already i.e. virus/trojan infected but requires payment to remove it ... which is what the trojan/virus scam is doing!! We do regular weekly backups so I'm assuming that the 'fail-safe' answer is to reformat the HD and reinstall from the backup (last one completed prior to FF problem)?? Any caveats and/or further advice welcome

TIA

That would be the nuclear option if you've got a good backup (or just use system restore). Thing is this isn't malicious in the sense of system damage, just annoying and may well have been bundled in with something you installed recently, FF add-in or plugin, might even be able to uninstall the thing via add/remove programs.

Take the computer off line, flush the browser cache of all cookies, reboot and restart the browser. Check the message has disappeared. Then reconnect to the Internet if all is well.

It sounds more like a home page hijack, these can attack any browser.

Have a look and see if you can change the home page, after clearing cookies etc.

Give this page a read - it has detailed instructions to get rid of the malware:

https://malwaretips.com/blogs/remove...support-virus/

Try a system restore on the PC back to a date some time before the problem occurred, that normally serves to remove any malware or similar.

Thank you all for your helpful advice, Particularly Le Pingouin's suggested tips page. Initially had a problem modifying the add-ons but uninstalled FF, re-installed and altered the add-ons and 'Robert was Dad's Brother!!' What a marvellously useful community this is!!:D:D:D

Glad to hear you managed to clean it out. Nasty stuff.

I feel windows defender is powerful enough. i haven't used third party anti viruses for long with same trust. trust its four years and defender hasn't created me a single issue os shall i say it has defended my system well enough. windows has configured a good enough tool.

I have had these kind of problems in the past but the system restore feature has come to my rescue.

regrding anti virus and MS defender I pay BT £10 a month for tech support which as I have a small business I feel is a good investment having helped with some tricky issue s in the past. BT bundle Macafee anti virus in with some of their Broadband packages but the tech support people said that they recommemded Defender instead if you are running Windows 10 as t did a very effective job and didnt interfere at all with Windows; so that seemed a pretty good endorsement. Mind you it is still a good idea to run a malware scan from time to time with one of the free Malware scan tools.

If something malicious has been installed on your machine it has been compromised. Wipe your HD and restore from back up - only way to be sure.