Hi! I've been using PrivateFirewall (PF) for some time, and tend to use it in a conservative fashion, blocking as much as possible and accepting the hassle of allowing things manually every time, rarely creating any permanent rules. This includes system access like opening files, and so on. I keep the firewall on the most restrictive settings possible most of the time. There is a problem though, I'm trying to use a compiler that I can not get to work without setting the Process Monitor slider to "Off". The compiler suite wants to open a lot of processes since it is using GCC. I've allowed everything or set it to "ask", but something apparently keeps getting denied access, which means the compiler can not start. How can I find out what is happening? I have already tried Sysinternals ProcMon while (successfully) running the compiler with PrivateFirewall off, to see all the processes that the compiler wants to start. I've made sure all those processes are added to PrivateFirewall's process monitor, and have permissions set to "Ask", but it doesn't help. As soon as I move the PF process monitor slider back to "Medium" or "High", the compiler will not work. Unfortunately, the compiler doesn't give any useful information either, it just thinks it has run out of memory (bogus). Please help me diagnose this problem, or recommend a different free firewall that is as good and fine grained (or even more fine grained) as PrivateFirewall. I'm on Win10 64-bit.