When I go to
Control Panel -> Hardware and Sound -> Devices and Printersit can take 5 minutes or more to populate the window. A green bar slowly progressing along the top.
Sometimes (not always) when I click on the Network icon it shows an empty window, taking five or more minutes, also with a green bar slowly progressing along the top. EDIT: After I submitted this post I saw that the network window had finally populated. Still, it was incredibly slow and happened after the window showed a message saying "This folder is empty."
If I go to This PC that comes up almost instantly, including the mapped network drives.
At first thought it might be a name server problem with the router but that checks out OK.
Any hints appreciated!