Firefox recently started opening unwanted websites specific: Zalando.nl). How can I block this?

Question

I do use a firewall, a virus scanner, ccleaner, spybot, keep them all as up to date as possible, running them on a regular and frequent basis, but I am still plagued by guerilla marketing techniques form Zalando.nl, a German-based seller of shoes and fashion, recently conquering the Dutch market. I never bought an item and manually removed any cookie I could find. Even a root kit scan by Avast did not solve the problem.

Answer 1

You can open the <b>about:config</b> page and search for prefs that are referring to <b>Zalando</b> and reset those prefs via the right-click context menu to the default value.
*http://kb.mozillazine.org/about:config
If you do not keep changes after a restart then see:
*http://kb.mozillazine.org/Preferences_not_saved
Create a new profile as a test to check if your current profile is causing the problems.
See "Creating a profile":
*https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
*http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues
If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.
*http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox
Do a malware check with some malware scanning programs on the Windows computer.<br />
Please scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of their databases before doing a scan.
*Malwarebytes' Anti-Malware:<br>http://www.malwarebytes.org/mbam.php
*SuperAntispyware:<br>http://www.superantispyware.com/
*Microsoft Safety Scanner:<br>http://www.microsoft.com/security/scanner/en-us/default.aspx
*Windows Defender: Home Page:<br>http://www.microsoft.com/windows/products/winfamily/defender/default.mspx
*Spybot Search & Destroy:<br>http://www.safer-networking.org/en/index.html
*Kasperky Free Security Scan:<br>http://www.kaspersky.com/security-scan
You can also do a check for a rootkit infection with TDSSKiller.
*http://support.kaspersky.com/viruses/solutions?qid=208280684
See also:
*"Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked