Occasionally, our websites that we host locally will all start generating 
errors.  There don't seem to be any memory issues.  There's nothing in the 
Event Log that's out of the ordinary.  But all at once, our sites will start 
generating errors like the one below.  Restarting IIS doesn't solve 
anything, but a full reboot does "solve" the problem, but is certainly not 
the best option.  It's happening quite frequently today and it's very 
difficult to debug because our priority is to get the servers back up and 
running as quickly as possible.  So I'm curious if anyone has come across 
this problem, or has any suggestions for what I can look for the next time 
that it happens.  The machine should be more than capable of handling the 
traffic it receives.

 Configuration Error
Description: An error occurred during the processing of a configuration file 
required to service this request. Please review the specific error details 
below and modify your configuration file appropriately.

Parser Error Message: Unable to load file '<Project/AssemblyNameHere>'.

Source Error:

Line 256:                <add assembly="System.EnterpriseServices, 
Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>
Line 257:                <add assembly="System.Web.Mobile, 
Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>
Line 258:                <add assembly="*"/> <~~~~~ This line is 
highlighted, in most cases.
Line 259:            </assemblies>
Line 260: