@Leray22222 This is a know behaviour - you can mitigate this by using a configuration backup/restore when switching modes.

@Targenor You can update the HW v8 FW to TL-WR841N(UN)_V8_170210 - from here. But I doubt that will bring IPv6 support to your router. If I'm not mistaken the IPv6 is available in TL-WR841N from HW...

@SSolheim Glad you've made it. By the way - resetting the device is in Step 3 of the troubleshooting guide I posted.

@Intracomp I don't believe you would be able to see a list of your registered DDNS names across several devices. TBH I've never tried to move a TP-Link DDNS name from one device to another. You can...

@DJDAN That's the ISP who makes that. Contact them and ask if they are giving you a public IP address on your modem. Another way to check that is to google in a browser "what is my ip address" and...

@DJDAN Configuring address reservation for your PC would be a good idea if its IP address is received by the modem DHCP. Follow the guide I posted for configuring virtual server (port-forwarding)....