Hi Dimitris (@dkoukoul),
It may be the case that a lower SDK version might fix the problem, but I think it would be preferable to try and resolve the issue with using the latest Core version.. perhaps you could give some further explanation as to what happens… does the EyeX no longer appear in device manager?
It might be worth trying a fresh install by uninstalling the old core version, removing Tobii settings (%localappdata%\Tobii)
and installing the latest core version.
Might also be worth testing if this issue occurs on another system as well. Thanks for your feedback.