Connected devices list is empty

I have a number of computers connected to my Comcast modem/router both wired and wirelessly The wired devices are connected through an unmanaged switch. But nothing shows up in my connected devices list. I have seen several posts about this same problem for a long time and the solution from Comcast always seems to be a hard reset which according to the users does not permanently correct the problem. Please tell me when we can expect a permanent solution to this ongoing problem.