I have a home network with devices running all flavours of Windows, plus NAS, plus networked printer, scanner and a Thomson wireless router that provides USB router based file sharing on its network.
I could not find the answer to a common network problem on the forum so here is my own solution.
When you install windows 8 you are given the choice of using a MS account or just a regular user account for log-in.
I was using a regular user account with Windows 8 prior to the upgrade to be consistent with the rest of my network.
When you upgrade to 8.1 you are channelled into using a MS account for the sign-in.
You do so and then experience problems with connections on your network that did not exist before - you can see the network locations but you cannot reliably, nor quickly use them, or not at all.
I first tried all the recommendations on the forum.
Then when trying to map a network drive for the umpteenth time I tried ticking the box "Connect using different credentials". I input my regular user account details and the problem was solved (I did not tick "reconnect at sign-in").
I now have normal service on my network.
This took me weeks to stumble upon - I hope it helps someone else.