I installed emacs 26 under cygwin64, terminal version, no X.
When I enter emacs to start there is a second or so delay before the bash prompt reurns, the error code is set to 0.
The same thing occurs with emacs 25.
I have two machines, one Win7, the other Win10. The behaviour above is exhibited only on the Win7 machine.
I am unable to find any log info to see what might be going on.