We have a .NET 1.1 Web Service that is set up for basic authentication
with a Keep Alive setting of 900 seconds (15 minutes). The Web Service
is running under IIS on Windows 2000 Server.

What we've been noticing lately is that when the Keep Alive time
expires the next Web Service call we make fails with a 401 error.

I may misunderstand, but I thought that the framework would handle
processing the 401 error by resending the credentials. However, what we
see in the IIS log is an attempt was made to authenticate with *blank*
credentials.

Does this sound familiar to anyone?