Hello, this is my first post here, hope I went for the right subforum. Also, I'm no linux expert, just know to do a thing here and there.

My problem is, that I can't access a NAS device (WD MBWE White Light) with BusyBox on it over Internet. It works localy though. When I connect remotely via SSH on putty, I get the message about server key, I accept that, then I am propted to enter user name, and then a password, but when I enter password the server returns "Access Denied".

So I tried to generate key, use that but the server refuses the key as well.

What am I doing wrong? Port 22 on router is forwarded onto the device. Obviously I can connect localy over LAN. Help me please.

Could it be that the router is running an ssh daemon, and that you're actually attempting to log in to the router rather than the NAT unit?

Check that the key matches the one displayed when you connect from inside the LAN.

No, the router is TP-Link TL-WR841ND running original FW, but will try to change the ssh port on the NAS and will try again. Thank you for the hint.

in your LAN is the NAS the ONLY device that can use ssh? also does your router port forward port 22 to the NAS and the NAS LAN IP only?

sounds to me that something other then the NAS is getting the ssh prompt and you are not providing the correct user/pw challenge for that device.

edit to add:

also check to see if the NAS has a log file for attempted logins. see if it really is showing bad user/pw combo and that it is configured to accept connections via WAN, not just LAN.