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Remove MacSter ads in Mac OS

Learn a profile of the infection that causes Ads by MacSter to appear on random web pages and get a set of instructions to remove it from your Mac.

MacSter is not quite a classic example of a computer virus but it’s definitely something that disrupts one’s Internet browsing activity. Technically speaking, this is an adware program designed to make its authors money by embedding advertisements into web pages visited on the compromised Mac machine. So, on the one hand, we’re dealing with an application that claims to provide useful data about products of interest, including price comparisons and coupons; on the other – it installs without the users clearly realizing they’re getting an extension as annoying as this.

The most widespread tactic through which MacSter installs onto Macs is being included in setups for other software; in this case, the main app is typically freeware, and the bundle is opt-out. However, it might be problematic to notice this trick going through as long as you stick to the default setup, which is why it’s more than a good idea to always select custom install terms in order to actually see what’s there and untick the unwanted stuff. Another known technique for propagation is via hacked or malicious sites, where a script displays some pop-up that you have to click otherwise no further action can be done, e.g. you cannot navigate away from the page. This way, the adware infiltrates the system as a drive-by.

MacSter website

MacSter adware adds an extension to Safari, Chrome and Firefox if these are used on the target box. The add-on monitors the victim’s online searches and website visiting history so as to display fairly relevant ads. The sponsored components that start to appear on arbitrary web pages include links to third-party services (often embedded in text strings on the site), coupons, banners, and video ads. You may as well encounter pop-under windows getting triggered when random objects are clicked. Ads by MacSter also appear both in the top and bottom sections of search results pages, clogging up the overall layout big time. Another downside of this unwanted program operating inside your Mac is longer page loading times due to lots of redundant graphics being displayed.

Ad by MacSter

Whether it’s difficult or relatively easy to get rid of the MacSter pest varies. In some scenarios, it suffices to uninstall the respective add-on from the affected browser. Sometimes, though, this approach is only temporarily efficient and the adware comes back. The cleanup part of this guide describes how to act in either situation and remove the infection being analyzed.

MacSter Ads manual removal for Mac

The section below highlights the methods to eliminate Ads by MacSter infection from the web browsers it affected. Please follow the recommendations in strict order as they are provided.

1. Cleanup for Safari

• Go to Safari –> Preferences –> Extensions. Find MacSter on the list and click the Uninstall button

Restart Safari. Open a few pages to see if MacSter ads are still there. If so, proceed to the steps below

• Go to Safari –> Reset Safari

• Make sure all the boxes are ticked on the interface and hit Reset

Resrt Safari

2. Cleanup for Google Chrome (if affected by the MacSter virus)

• Open Chrome and go to Window –> Extensions. Look down the list and locate MacSter on there. Once found, click on the trash bin icon next to this entry

Restart Chrome. If Ads by MacSter still appear on visited pages, move on to the next step of this removal sub-section

• Click Options

• Select Under the Hood tab, then click Reset to defaults button

Reset Chrome

3. Cleanup for Mozilla Firefox (if affected)

• In Firefox, go to Tools –> Add-ons

• Hit the tab called Extensions on the left. Locate MacSter on the list and click the Remove button next to it

Restart Firefox and see if it helped. If not, proceed to the tips below

• Open Firefox and select Help –> Troubleshooting Information

• On the page that opened, click the Reset Firefox button

Reset Firefox


Get rid of MacSter adware using Combo Cleaner automatic removal tool

The Mac maintenance and security app called Combo Cleaner is a one-stop tool to detect and remove MacSter ads virus. This technique has substantial benefits over manual cleanup, because the utility gets hourly virus definition updates and can accurately spot even the newest Mac infections.

Furthermore, the automatic solution will find the core files of the malware deep down the system structure, which might otherwise be a challenge to locate. Here’s a walkthrough to sort out the MacSter ads issue using Combo Cleaner:

  1. Download Combo Cleaner installer. When done, double-click the combocleaner.dmg file and follow the prompts to install the tool onto your Mac.

    Download Combo Cleaner

    By downloading any applications recommended on this website you agree to our Terms and Conditions and Privacy Policy. The free scanner checks whether your Mac is infected. To get rid of malware, you need to purchase the Premium version of Combo Cleaner.

  2. Open the app from your Launchpad and let it run an update of the malware signature database to make sure it can identify the latest threats.
  3. Click the Start Combo Scan button to check your Mac for malicious activity as well as performance issues.

    Combo Cleaner Mac scan progress

  4. Examine the scan results. If the report says “No Threats”, then you are on the right track with the manual cleaning and can safely proceed to tidy up the web browser that may continue to act up due to the after-effects of the malware attack (see instructions above).

    Combo Cleaner scan report – no threats found

  5. In case Combo Cleaner has detected malicious code, click the Remove Selected Items button and have the utility remove MacSter ads threat along with any other viruses, PUPs (potentially unwanted programs), or junk files that don’t belong on your Mac.

    Combo Cleaner – threats found

  6. Once you have made doubly sure that the malicious app is uninstalled, the browser-level troubleshooting might still be on your to-do list. If your preferred browser is affected, resort to the previous section of this tutorial to revert to hassle-free web surfing.

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