In Admin mode, system settings / generall, when I try to save it saysAccess to the path 'C:\EPiServer\Sites\Nykoping.InternWeb\Nykoping.InternWeb.Community\web.config' is denied.
Any ideas why?
The account under which the appliction runs needs modify rights to the config file. If it runs under application pool identy you can set modify rights for the IIS_IUSRS group.
But I would recommend editing the config file in an text editor instead.