Hello --

I have developed a web service that connects to SQL Server, retrieves 
data, and returns an XML String from a StringWriter through 
DataSet.WriteXML().  That XML String is read into a StringWriter and 
turned into a DataSet through ReadXML() to be used on the client side.  

My problem is pretty strange.  Occasionally, the data that comes back to 
the client is incomplete.  I have experienced missing columns and one 
occasion of a missing row.  Since the error is client-side, that says to 
me that the data is successfully retrieved, successfully turned into XML, 
successfully transmitted across the internet, and successfully read into 
the client-side DataSet.  It is not until the DataSet is accessed that 
there is a problem.  Most commonly, the error that occurs is that a column 
name does not exist inside the DataView, although sometimes the error is 
that the table does not exist inside the DataSet.

Interestingly, this only appears to occur when a web application accesses 
the web service.  If a Windows Forms application accesses the web service, 
there does not seem to be a problem.  It seems like I can reduce the 
problem by running the web service and web application in High (Isolated) 
mode and shutting off the Session variable on the web service.  Sometimes 
even that breaks, and I have to restart IIS...

I am making a guess that this has to do with some kind of threading 
issue.  No errors occur when the web service is accessed in a thread-bound 
window, and the errors appear to get better when the web service and web 
application are run out-of-proc.  

We're stumped by this one.  Has anybody ever experienced anything like 
this??

Thanks,
Robert Herrick