Short bio

OSX.FakeFileOpener is Malwarebytes’ detection name for malware that advertises PUPs and targets MacOS systems.

Type and source of infection

OSX.FakeFileOpener sets itself as the default application to open a huge amount of file-types and promotes the uses of potentially unwanted programs known as system optimizers. It does this by shwowng an imitation dialog for file-types that have no other default application listed.

fake “no app for this file-type” dialog

OSX.FakeFileOpener is distributed by the same websites that also promote the “system optimizers” by scaring users into thinking their system is infected.

scareware site



Malwarebytes for Mac detects and removes OSX.FakeFileOpener.


Malwarebytes for Mac will detect and remove the components of this malware.

Download and install the latest version of Malwarebytes for Mac.

Click the “Scan Now” button to perform a system scan.

If threats are detected during the scan, a count of detected threats is displayed. More detailed threat information is displayed after the scan completes.

Click “Confirm” to move the detected threats to Quarantaine.

If a restart is required to complete remediation of threats detected during a scan, you will be notified. When a restart is required, please remember to save all work before clicking “Restart”.

Associated threats


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