On the 2850 there is a 'customized' option so one can do DDNS with services that are not listed.

I've just discovered that the 2860 seems to have lost this

Is there any way to access the old facility somehow - like Telnet?

I'm running firmware 3.7.4.2 and I see the "customised" option at the bottom of the service provider pull-down list.

Thank you - that is a great relief. I have 3.7.4 on a newly delivered unit.

I will update it. Thank you

use the *rst* file extension for a clean / fresh install & back from the begin manually the settings to avoid previous firmware conflicts

Are you serious! That would be a lot of work, to put it mildly.

I just set up the router a few days ago, migrating it from a 2820. It took well over 2 hours.

What are the issues?

was just mentioned the *rst* file extension is the best option to update because is avoiding previous bugs & it sets back to factory default all settings ... thats all
If you have so many settings to do, i know is hard