Cryptic WSE 2.0 Error (WSE032 "configuration error" and System.Net.Dns.GetHostName())

While I was teaching my .NET Web Services class tonight I stumbled upon an esoteric error with WSE 2.0 that I had not encountered before - an error that ruined two demos of mine. I had tried the demos literally 15 minutes before class and theyh worked great. When I had a full classroom, though, it crapped out. The error message I got was the standard WSE032, saying:

An unhandled exception of type `System.Configuration.ConfigurationException` occured in microsoft.web.services2.dll

Additional information: WSE032: There was an error loading the microsoft.web.services2 configuration section

This is a pretty common error message when something has gone awry in WSE. For example, if you are using UsernameToken authentication, but mistype any values in the Web.config file you`ll get this error. What was a bit perplexing was that, (a) the demos had worked earlier, and (b) the stack trace of the error message referred to a problem with System.Net.Dns.GetHostName(). As I said, my demos bombed out, but afterwards I did a quick search on Google and found this blog entry: WSE 2.0 (sp1 & earlier) - The mistory [sic]of error code WSE032.

This blog entry had a fix for my problem. It appears that WSE uses the GetHostName() method, and this caused some problems, perhaps because my computer`s wireless connection died, or my DNS entries timed out, or something. Anywho, the solution - which worked for me - was to add a line to the HOSTS file in C:\WINDOWS\system32\drivers\etc. This did the trick. Probably the most esoteric bug I`ve faced in my experiences with Web services.