I have set up the runtime on my laptop but when I start the server and try to open the demo site map, it tells me webpage is not available.
The demo is a separate download. Did you download the Demo from here and install as described in the README.txt?
Which version of OH?
Yes, from that link and OH2.
When I start the runtime it works alright but when I try accessing the demo sitemap and it tells me webpage is not available
Added an openhab2 tag to this posting.
I assumed you were using OH 1. I’ve no experience yet with OH 2, though now it is in beta I might take the plunge the next time I can put 60 minutes next to each other to work on something.