I had this problem in past . Then I tried reinstal programs ...tried different kind of postprocessors .. nothing ! Found only one solution - Format C for whole Windows. But this steals so long time ...and only a few months have passed...and again!
Ok .. about problem ! Everytging is work fine - I can create a model , calculate toolpath , madcam simulator is showing how it will be .. But when I try save it in G code, I have end message without necessary time, and text file with code does not generated, and does not saved . It looks like it

madCAM report:
Created on: 3/22/2019 10:41:00 PM

=========== Programmer notes ============

Programmed by: xxx
Maximum Tool Length:
Approximate work piece dimensions: L=13; W=22.381; H=23.451

=========== Toolpath Specifics ============

Tool: T12 ( D3.175_r0.050_L25.000 ) TaperLabais10
Path: Between_Curves

============= Code ==============

File successfully written as D:\CNC\xxx\1.ngc
Post Processor:C:\ProgramData\5XCNC\madCAM\5.0\Post Processors\LinuxCNC_Metric_5-axis.txt

Tool changes: not specified in post processor
Rapid traverses: not specified in post processor

Everything is ok , but without matching time and g code in end.
If someone can give a solution without format C, I will be very thankfool!