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My PC has been infected with a malware that opens pop-up to some ads, mostly in my native language (Persian) but from (wonderlandads.com), when I click on a link or in an input box in StackExchange websites. Interestingly, it just occurs for these websites and no other website! It occurs in both Firefox and IE
I scanned my computer with NOD32 7.0.2 , and some freeware malware scanner (kaspersky tools,...), but they couldn't find it. I reinstalled the Firefox and disabled startups but couldn't fix it.
What is the cause? and what can I do?
How it can hide itself from powerful antiviruses and anti-malware?
Update It seems I could handle it by killing running processes and refreshing the firefox.