Web Services deployment error "Server returned nothing (no headers, no data)" and more

Question

I'm developing a large-scale VI with an associated web service VI in 2010 SP1. The "auxiliary VI" is responsible for data capture and analysis as well as communications and data storage. It is fairly large and communicates with the web method VI via network-shared variables [and I'm using the DSC module to allow event handling on the shared variables].
I can build and deploy the web method VI just fine and it runs great. However, I need to communicate between the auxiliary and web method VI's, and it looks like I can't do that without including the auxiliary vi in the RESTful web service build [by the way, is there any way to do this with web service builds?]. When I added the auxiliary vi to the build, it built fine, but then during the deployment I got:
"Server returned nothing (no headers, no data)"
The next time I tried to deploy, I got a spurious NI Auth dialog per this KnowledgeBase article. Following the instructions for case 1 ["Application Web Server failure since last start"], I ran Services.msc and found that NI Application Web Service was indeed not running. I tried to restart the service but got this error:
"The NI Application Web Server service on Local Computer started and then stopped. Some services stop automatically if they have no work to do, for example, the Performance Logs and Alerts service."
The KnowledgeBase article suggests restarting at this point and I did, but I still see the same behavior. So I really have a few questions:
1. Is there any way to deploy a network-shared variable library across a deployed web service and local VI?
2. What causes "Server returned nothing (no headers, no data)" upon deployment? A google search returned very little.
3. What does this mean: "The NI Application Web Server service on Local Computer
started and then stopped..." and what do I need to do to get my Application Web Server back up?
[to heap on the pile... I tried to re-enable the Application Web Server from localhost:3580 and got an error. Then localhost:3580 went off-line also.]
thanks!
Solved!
Go to Solution.

Answer 1

Update.
I noticed that the Application Web Server was trying to deploy the broken web service and was choking on it. There seemed to be no way to erase the .lvws originally created by the build. I could delete the deployment folder at $(WebServicesRoot)\UserServices\deployed\<Service Name>-<Globally Unique Identifier (GUID)> but it was recreated from the .lvws every time I attempted to restart the service.
So I called NI and they pointed me to this directory [in XP]:
C:\Documents and Settings\LocalService\My Documents\LabVIEW Data\WebServices\Standalone
The .lvws was in this folder. I deleted it and now I can run the ApplicationWebService. Apparently this undocumented hidden file is a "not-quite-bug" that is recognized as needing a fix in upcoming releases.