After installation it was possible to see the printer from Studio (including video) including controlling it.
The day after, there was no printer visible in Studio. It is visible in BambuHandy app (on both mobile and pad) and can be communicated with and e.g. move the bed. In Studio the Device tab does not show any printers.
I can successfully ping the printer from the PC.
I have also reinstalled the Bambu Studio on PC, and also the Handy app, to no avail.
It seems that the printer is not visible to the Bambu server, or something.
If the Handy App can see it, then it is visible to the Bambu cloud server. Have you tried logging out of both the printer and the Bambu Studio app and logging back into both?
Yes, I have tried that, i.e. quit the network on the printer and re-established connection and also closed and reopened Studio on the PC. Still no printer is shown in the Studio Device tab.
Sounds like the firewall on your PC is blocking it. I would try turning off the firewall completely just to see if that is the issue. If it works, you will have to find out what is blocking it or give Bambu Studio permissions.
I have not heard anything from you so I try again:
Turned off the firewall completely
Installed Bambu Studio on anoter PC
Pinged the X1 from the PC (which worked ok)
What can be done to get me online with the printer?
Just printing with data on the SD card is rather limiting as any temperature/fan settings do not seem to be passed to the X1 (when selecting filament it only uses the default values).