Rising Firewall

This is not popwnd.exe but popwndexe.exe and that is...I think...tray client of fw. It can't be disabled from msconfig because of one reason - such trick is often used by malware to disable or bypass security software. This feature is connected with option "Self protection" in "Other settings" tab that is default enabled.
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In fact Rising Fw is not very light....but it's lightweight enough not to be
inconvenient. I find that even its 4 processes aren't especially noticeable in daily work.

 

Thanks for clarifying it's purpose.