Ok I was too impatient. It seems to take some hours before everything becomes healthy. So the new IP address was not a problem in relation to that. But it still eats a lot of resources on my laptop even though it does "nothing". It is convenient to be able to do experiments on your laptop, but apparently I should consider installing UMH on a separate box. What do you guys do out there? (except for production environments, which are obviously not running on laptops).