Q: Pop up ads and websites, since loading OSX ElCapitain latest

Click here and follow the instructions, or if there’s a type of adware not covered by them on the computer, these ones. If you'd rather not remove it manually, you can instead run MalwareBytes for Mac.

MalwareBytes simplifies the process of removing adware but doesn't stop it or other malware from getting onto the computer. It shouldn’t be relied on to prevent future incidents; instead, avoid downloading software from sources other than the Mac App Store or the developer websites.

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It's not because of the update to OS X.  You have adware on your computer, and you have two options for getting rid of it:

• Download Malwarebytes' Anti-Malware for Mac.  It was developed by a trusted and respected contributor here.  It's a simple, non- intrusive program that deletes known malware/adware from your hard drive.  That's all it does.  It doesn't add anything and it doesn't take away anything else.
• Follow the directions in this Apple support article to remove it manually --> http://support.apple.com/en-us/HT203987

In the future, avoid downloading anything from torrents or from aggregate websites like CNET, Download (dot) com, MacUpdate, Softpedia, Softonic, etc.  Only download from the Mac App Store or the developer's own website.  That's how you prevent this from happening.

You may have installed ad-injection malware ("adware").

Don't use any kind of "anti-virus" or "anti-malware" product on a Mac. There is never a need for it, and relying on it for protection makes you more vulnerable to attack, not less.

Back up all data first.

Some of the most common types of adware can be removed by following Apple's instructions. But before you follow those instructions, you can attempt an automatic removal.

If you're not already running the latest version of OS X ("El Capitan"), updating or upgrading in the App Store may cause the adware to be removed automatically. If you're already running the latest version of El Capitan, you can nevertheless download the current updater from the Apple Support Downloads page and run it. Again, some kinds of malware will be removed—not all. There is no such thing as automatic removal of all possible malware, either by OS X or by third-party software. That's why you can't rely on software to protect you.

If the malware is removed in your case, you'll still need to make changes to the way you use the computer to protect yourself from further attacks. Ask if you need guidance.

If the malware is not removed automatically, and you can't remove it yourself by following Apple's instructions, see below.

This easy procedure will detect any kind of adware that I know of. Deactivating it is a separate, and even easier, procedure.

Some legitimate software is ad-supported and may display ads in its own windows or in a web browser while it's running. That's not malware and it may not show up. Also, some websites carry intrusive popup ads that may be mistaken for adware.

If none of your web browsers is working well enough to carry out these instructions, restart the computer in safe mode. That will disable the malware temporarily.

Step 1

Please triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:

~/Library/LaunchAgents

In the Finder, select

          Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. Press return. Either a folder named "LaunchAgents" will open, or you'll get a notice that the folder can't be found. If the folder isn't found, go to the next step.

If the folder does open, press the key combination command-2 to select list view, if it's not already selected. Please don't skip this step.

There should be a column in the Finder window headed Date Modified. Click that heading twice to sort the contents by date with the newest at the top. If necessary, enlarge the window so that all of the contents are showing.

Follow the instructions in this support article under the heading "Take a screenshot of a window." An image file with a name beginning in "Screen Shot" should be saved to the Desktop. Open the screenshot and make sure it's readable. If not, capture a smaller part of the screen showing only what needs to be shown.

Start a reply to this message. Drag the image file into the editing window to upload it. You can also include text in the reply.

Leave the folder open for now.

Step 2

Do as in Step 1 with this line:

/Library/LaunchAgents

The folder that may open will have the same name, but is not the same, as the one in Step 1. As in that step, the folder may not exist.

Step 3

Repeat with this line:

/Library/LaunchDaemons

This time the folder will be named "LaunchDaemons."

Step 4

Open the Safari preferences window and select the Extensions tab. If any extensions are listed, post a screenshot. If there are no extensions, or if you can't launch Safari, skip this step.

Step 5

If you use the Firefox or Chrome browser, open its extension list and do as in Step 4.

Oisin Creagh wrote:

 

Thanks Pinkstone. It was started up again by the download of the updated system.  I had managed to get rid of the problem before, but something in the new upload DID trigger this new problem.

Apple does not release updates to their operating systems that contain adware or malware.  That would be wildly and horribly irresponsible of them.  So I'm sorry, but you're wrong.  Updating your OS did not cause adware to be installed on your hard drive.  It was already there.  You clearly didn't get rid of it as well as you thought you did.  It's no matter though — follow the steps outlined in this thread to remove it, and in the future, don't download things from disreputable sources like torrents and aggregate download sites.  Only download apps/plugins/extensions/drivers from the Mac App Store or the developer's own website.  Don't download anti-virus programs or "maintenance" programs either, as many times the installers of those are bundled with adware.

If you would care to provide the screenshots that I asked for, this problem can be cleared up in a few minutes.

Oisin Creagh wrote:

 

…It was only after the problem occurred at the time that I discovered from online searching that this POP-UP  is a huge problem facing APPLE users. Shame it cannot be brought under control.

FWIW, first, it is not a virus, and second, it has not been a "huge" problem for me. As matter of fact I have never had any malware/adware. One has to install adware/malware knowingly or unknowingly.

Oisin Creagh wrote:

I purchased a MAC last summer, partly to overcome the problems with virus's etc on PC's.  Within weeks I was confronted with a clever pop up, formatted to look like it came from Apple, saying I needed to run a speedtest (or some such message).  In my innocence, I thought Apple were free from such crap and that this was a MAC message, like the regular calls for updates.  This was clearly where the problem came from, and I accept this.  I over estimated the APPLE resistance to attack, having being sold it as a 'computer that needed no virus protection'.  It was only after the problem occurred at the time that I discovered from online searching that this POP-UP  is a huge problem facing APPLE users. Shame it cannot be brought under control.

It's not a "huge" problem, though.  What you described is a browser hijacker, and they're easy enough to dismiss — you Force Quit Safari ( --> Force Quit --> Safari), then restart Safari in Safe Mode by holding down the Shift key.  This prevents previously opened tabs/windows from reopening.  It wasn't a virus, because there are no viruses for OS X. 

Stopping these pop-ups from taking over your browser is a simple matter of staying away from the kinds of sites they're known to inhabit, such as XXX sites, torrent sites, mp3 download sites, or website that offer the ability to do or download something for free that you know would otherwise cost you money.  Disreputable sites do disreputable things.