I've connected a Mac mini to a PC running Windows via Ethernet. Both computers have manually-configured static IP addresses. I was able to use Samba on the Mac to connect to a shared folder on the PC the first time I tried with no problem. I connected and disconnected multiple times, leaving the connection open when I restarted the Mac. After restarting, I can no longer connect via Samba. I get the generic "There was a problem connecting to the server ...." error message.
Where might I start with troubleshooting? What could be the issue?