Zapchast puts a copy of itself in the registry as a Window's runkey so that is it activated when Windows starts. When active, this trojan will execute another trojan, Trojan.Pakes, which downloads other malware.
Spyware Doctor can automatically remove the Trojan. Even if you remove it manually, we recommend you should use Spyware Doctor to make sure it's completely removed from your system and will not be reinstalled by itself.
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