KAV does seem to block downloading of infected files with ftp.
The downloads fail on first transfer attempt (KAV intercepts) but if the ftp client has automatic retry then the infected files downloads successfully on the automatic retry. Ticking "Disabled ftp restarts" in the ftp proxy server does not prevent the infected files getting through.
The client PCs on the LAN use WGIC, transparent proxy is set in WinGate.
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