You need kaspersky or something like that.It happened to you because you were infected.
The Trojan.Generic could come back on your PC or Mac several times if you do not manage to detect and remove its hidden files and main objects.We suggest that you download an advanced removal software for your computer as it will scan for all types of malicious objects, installed with it. Removal attempt with a professional cleaner for Mac or Windows can happen in about 15 minutes time and may save you hours in trying to uninstall Trojan.Generic by yourself.