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What to do if my computer is infected by a virus or a malware?
I've had a few cases recently where I downloaded an installer from the internet and that the install fails with the message that the file checksum is incorrect (or something to that effect). Also recently my gmail was hacked from somewhere in Russia. I get the feeling maybe some process is tampering with the files and maybe someone is recording my keystrokes.
I did install a cracked version of some software, could it be that that came with some malicious software that is now listening in on my computer and touching files I download.
I've installed AVG and SEcurity Essentials and both give no alarm. But is could be that they just don't know about this particular threat.
What are other ways to check for malicious software? Check for open ports, rootkits etc?