I had recently been experiencing intermittent problems with Radio UserLand on my laptop. Occasionally the Radio UserLand and its local webserver would fail to load correctly. After a reboot the problem would disappear but would return a day or so later. Finally the problem was diagnosed: A clash with the really excellent news aggregator SharpReader. Both Radio UserLand and SharpReader attempt to listen for connections on port 5335. Radio UserLand uses this port as its fixed local webserver port in addition to port 80 or a user defined alternative. SharpReader uses port 5335 to allow it to receive subscription information when a user clicks a Radio UserLand icon in a web page.
The solution is simple. From the General tab on SharpReader’s Tools:Option menu, deselect the option “Listen for subscriptions on port 5335” and harmony is restored.
Why was the problem intermittent? Quite simply because, like many people who tire of waiting for Windows to boot or who find themselves running short of RAM, I prefer to start most programs manually, on demand, instead of allowing them all to load at startup. In this case, whichever of Radio UserLand or SharpReader was manually started first claimed the port and the other one lost out.