http://www.clamxav.com/ free malware scanner for Mac OS X https://discussions.apple.com/docs/DOC-3291

You can also try https://www.malwarebytes.org/antimalware/mac/index.html

If we assume that the redirect is embedded in the web page, there are a couple ways that could happen.

(1) A bad extension. You can disable nonessential extensions on the Add-ons page. Either:

• Command+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then cast a critical eye over the list on the right. None of these come with Firefox, all are optional. If in doubt, disable.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

(2) A hijacked connection. Could you check the setting here:

"3-bar" menu button (or Firefox menu) > Preferences

In the left column, click Advanced, then on the right side, select the Network mini-tab and click the Settings button. You can try "No proxy" here.

Thanks jscher for specific instructions that I could understand and follow. Unfortunately the first fix you suggest told me I don't have any add-ons and the second was easy enough to implement, but didn't fix the problem.

I'm afraid the multiple websites to which my other correspondent directed me flooded me with so much information on which I don't know how to act that I am left feeling the internet is such a dangerous and hostile place that my best course of action would be to retreat to a darkened bedroom, pull the covers over my head and never click on another website, because I don't know where malware might be lurking.

Re specific recommendations on how to get rid of the Firefox redirect virus, do you think I should uninstall Flash? Would doing so prevent various aspects of the internet from working? Has removing Flash worked for others in similar circumstances?

FredMcD said

http://www.clamxav.com/ free malware scanner for Mac OS X https://discussions.apple.com/docs/DOC-3291 You can also try https://www.malwarebytes.org/antimalware/mac/index.html

Malwarebytes sounds good, but after reading the enormously long, finger-wagging discussions.apple.com article about how dangerous it is to download ANYTHING I am reluctant to trust it!

SuperSue said

Re specific recommendations on how to get rid of the Firefox redirect virus, do you think I should uninstall Flash? Would doing so prevent various aspects of the internet from working? Has removing Flash worked for others in similar circumstances?

At this point, I don't know exactly what is wrong with your Firefox, so it's difficult to predict the effect of different changes.

It's easy to disable websites from using Flash by changing a setting on the Add-ons page. Either:

• Command+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. On the right side, set any plugin that doesn't have an immediate use to "Never Activate" to hide them from websites. In some cases, this only takes effect in a new window (which you can open from the menu or using Cmd+n).

Later you can upgrade plugins you find important to "Ask to Activate" permission. With that setting, when you visit a site that wants to use Flash, you should see a notification icon in the address bar and usually (but not always) one of the following: a link in a dark gray rectangle in the page or an infobar sliding down between the toolbar area and the page.

The plugin notification icon in the address bar typically looks like a small, dark gray Lego block. (If it's red, Flash needs updating.)

If you see a good reason to use Flash, and the site looks trustworthy, you can go ahead and click the notification icon in the address bar to allow Flash. You can trust the site for the time being or permanently.

But some pages use Flash only for tracking or playing ads, so if you don't see an immediate need for Flash, feel free to ignore the notification! It will just sit there in case you want to use it later.

OK, have done this, leaving only

OpenH264VideoCodec provided by Cisco Systems (automatically installed by Mozilla) and NortonInternetSecurityBF as "always activate".

The problem still exists -- although the websites to which it redirects me do appear to have changed. Now I am redirected to a website called Searchadsredirect.com which offers to sell me the means to get rid of the malware that forced me to go to it ....

What a pity the genius and intensity so clearly possessed by malware writers can't be put to some use other than lining their own pockets .... And can't Mozilla find and prosecute the owner of the website Searchadsredirect.com which hangs out at

http://findingresult.com/?id=9PO98WX17&dn=searchadsredirect.com&rpid=9PO4101L9

SuperSue said

Now I am redirected to a website called Searchadsredirect.com which offers to sell me the means to get rid of the malware that forced me to go to it

That is called Ransom-Ware. Check out these links; https://www.bing.com/search?q=Searchadsredirect.com&pc=MOZI

OK, I don't understand the material in any of these links, partly because most of them are in languages other than English. But yes, ransomware seems a good name. Only one of the sites promising a fix is free and, as mentioned, after this experience I don't trust that site.

So at this point I'm about ready to give up on Firefox and retreat to routinely using the otherwise-inferior Safari. I do realise that the contributors to this forum are volunteers, not employees of Mozilla and I thank them very much for trying to help. However, presumably Mozilla does monitor this forum (?) So guys, if you're there, at the moment this problem only occurs for me with your browser. From the German, Polish etc websites in scher2000's links, it seems that I am not the only sufferer. So I think the guts of it is that if you want people to keep using Firefox, you need to figure out how to fix this and hopefully upload some effective cleaning fluid and protective technology. Otherwise we will all just have to consign your beloved baby to the trash can of history in order to save our own miserable skins. Disappointing I know, but needs must when the devil drives -- and these malware artists are the very incarnation of the devil.

Were you able to run the Malwarebytes Antimalware cleaning software?

https://www.malwarebytes.org/antimalware/mac/

I haven't downloaded it, because I don't trust it not to make things worse. Norton antivirus can't find anything, so ....

Have you downloaded the Malwarebytes thing and can vouch for its safety?

I have used Malwarebytes Antimalware (free version) on Windows from time to time, but I don't have personal experience with the Mac version.

My opinion has not been swayed by free appetizers at the company's party at last year's RSA security conference. ;-)

Free appetisers?? It must be OK then!

I have downloaded it but can't get it to move from my Downloads folder (it didn't give me the option of putting it anywhere else) to the Applications somethingorother, as prescribed.

I am relatively new to Macs, having bought my first one ever late last year because I hated Windows 8 so much. ( I have been greatly disappointed, as contrary to the urban myth that Macs don't get viruses I have never in 25 years of PC use had this sort of virus problem. And while I'm bleating, again contrary to the urban myth that Macs are better at graphics, there doesn't seem to be any graphics program available that's half as good as Corel Draw, which isn't available for Macs). How do I even open my Downloads folder?? There's an icon in the bottom toolbar but double clicking on the file containing the antimalware thing doesn't seem to do anything ....

OK, I've managed to get MBAM-Mac-1.1.3.72.dmg into my Applications folder, but now double clicking it just brings up a popup box telling me to drag it to my Applications folder ....

AAND now I've managed to install and run it. It found nothing. So I followed all the supplementary instructions up to and including:

The DNS Servers box will contain at least one IP address.. If the addresses can be selected within the list, they are set by your computer. Remove those addresses (select them and click the '-' button below the list). Your computer will now be set to obtain its DNS server settings from the network. If the problem you are experiencing goes away at this point, you may stop here, otherwise continue reading.

If the addresses shown are displayed in gray text, they being assigned by the network. In this case, you will need to change the settings in your network hardware, most likely your wireless router. See:

https://support.malwarebytes.org/customer/portal/articles/2049288-?b_id=9511

If you are not in control of the network, or wish to verify that the network is the source of the problem, you may try adding custom DNS servers to this list, which will replace the settings provided by the network. You may insert either the OpenDNS server addresses (208.67.222.222 and 208.67.220.220) or the Google DNS server addresses (8.8.8.8 and 8.8.4.4). (Click the '+' button to add each server address.)

If the problem persists after changing your DNS settings to use the OpenDNS or Google DNS servers, it is not the result of a DNS problem.

Well I can't select either of the two IP addresses in the DNS box, and 8.8.8.8 is already one of them. So I'm not sure what to do about that ....

But in any case, I return to my original thought that the router is the problem. I contacted the router manufacturer before I tried you guys. They were in China and I couldn't understand their English. They tried to help by email -- and I thought they had for a bit, probably by sending a firmware update to the router -- but then the problem came back and the Chinese people stopped talking to me.

The router IS quite old and I suspect the only lasting fix will be to buy a new one. Or I could just stop using Firefox. At the moment that seems like the cheaper and easier option.

Hi SuperSue, unfortunately as a Windows user I suspect none of the things I would suggest to do are applicable to Macs.

You may want to "trash" the Firefox application (but not removing your data, such as bookmarks) and install it again from:

https://www.mozilla.org/firefox/all/

All right, why not -- just tried trashing and reinstalling Firefox -- no change to problem.