It didn't used to do this (a long time ago)...but has for about the past couple of years. Running on: CYGWIN_NT-6.1 Athenae 2.10.0(0.325/5/3) 2018-02-02 15:16 x86_64 Cygwin Win7SP1x64. If I do an 'ls -CF', as a "normal user" no admin privs (did a dropmyrights and verified that I only had traversal priv), of /proc/sys/Global\?\?/, it will blue screen my system every time. I didn't really want to even look for it, but finally decided to try it as an unprivileged user -- to see if that was an issue. Attached is a cygcheck.out. Thanks... -l