We have a small office network of about a dozen local PCs on a domain with another 5 remote users. I’m told by my ISP that it appears that at least one of my computers has been hijacked and is sending out intermittant spam at a low level. I’ve sat at most of the pCs and checked them out with both Symantec Antivirus and Malwarebytes. I found 1 PC with a lot of MyWebSearch type malware (256) and cleaned it out. How can I tell which of the computers has been hijacked and if we are no longer compromised? We have a limit of X MB/3-hour period. If this limit is reached, our ISP shuts down all outgoin mail for 3 hours before it is resumdn. Any suggestions?
