Laptop driver issues

[Buddy41]

Hi,
Please bear with me whilst I explain.
I use a small key cutting machine which is 12v
Connected to it is a small note book running windows 7 32 bit.
The note book which uses a software programme sends the relevant into to the key cutting machine by the way of a usb cable.

The key machine has a jack port which accepts a barrel lead fitting 5.5 x 2.1
Currently IÂ’m using it with a 12v supply direct from the vehicle battery.
Also in the vehicle is my inverter of which in the past I would also use.
The other day I removed the 12v battery leas from the key machine & connected the 12v supply lead from my inverter. I switched on the machine & my laptop showed a message when I tried to run the software saying driver not installed.
Looking in device manager I see Com 4 not available, Code 10, maybe driver not installed or could not be started.
I remove this inverter lead & connect the 12v battery lead & all fine. Connect the inverter leas again & same situation. I never touch the used leas but I changed it anyway but never made any difference.
The driver from the machine supplier is a prolific serial to ?
Anyway I reinstalled the driver but the same. Supplier sent me latest driver but still the same.
I have another note book exactly the same so I swapped it over but still the same.
I have a laptop in the house with windows 10 on it so I tried that & what I found is that when I switched the machine in all I could hear was ding ding ding all the time like the sound when the pc recognises something has just been connected.
Last test was to unplug the power adapter which connects to the inverter & using an extension lead used the house mains & that worked fine.

Something I also noticed.
When running the machine off 12v battery lead in device manager I see no Com4 mentioned at all.

When I connect the inverter lead then Com4 is shown but no driver etc.
Why does one run ok but no Com4 is shown but then when I connect the other itÂ’s then listed ?

Inverter connected shows Com4 but no drivers installed.
12v supply all works fine.
So is the old river installed or not ?

Very strange.
Inverter is pure wine wave 500w - 1200w
Key machine is only 60w

Thanks.