Hy Brianna,
i thanks for your reply but i found my reason!

i changed in my netwotk the computer name.

So this is not a good idea when you like to work with mach4.

In my experience with bigger control systems like siemens and ohter one there is no problem if you like to change anything else! Out of this information i can tell you that it gives a lot of points where you can hang on a licence without getting trouble with an Windows update or an change of an computer name...!

For my taste for example there is the ID Number of the CPU, the harddisk / drive, the MAC adress of the networkcard....! In Sum of this stuff you get an reliable ID.
It´just an overview what´s possible.
In my case i changed the Name back!

I know how it work´s with the licence handling on the machsupport.com homepage. But thanks for your Info. I just remember: maybe i´m wrong but was it limitet how often you can change your system / licence ( Mach4 Hobby Version)?!?
I´m not shure but when yes, then i disagree that the solution of licencing is the best for the future of mach4.
