I have a strange problem:
one (older) N900 can connect to a WLAN from NETGEAR, the other (younger) N900 cannot connect.
The only difference between both is, that the one that can connect, has a SIM card inserted and the other has no SIM card.

It is also very strange, that the one (younger) N900 that cannot connect to this router, can connect to a another LTE/WLAN router.
So WLAN is working in principle and the router has the correct
config.
The non working N900 does not even display the NETGEARs WLAN!