Web services and ADO SQL trouble

[ArturoSH]

I have some trouble to connect to a SQL database through a web service. I'm stuck because when I run the VI from the labView front panel or the block diagram, everything works well (he ODBC connection works with no errors). I just don't understand why when the VI is executed from the web service I get an error in the same Open.vi that worked well from labView.

Here is the response I get in my browser window when I execute the following Method URL:

http://127.0.0.1:8080/Digital_Output_Web_Service/Digital_Output_Events_6501_-_Dev4?Status=0&Line=0&P...

<?xml version="1.0"?>
-<Response>
  -<Terminal>
    <Name>error DAQ</Name>
    -<Value>
      <Name>status</Name>
      <Value>0</Value>
      <Name>code</Name>
      <Value>0</Value>
      <Name>source</Name>
      <Value/>
    </Value>
  </Terminal>
  -<Terminal>
    <Name>error SQL</Name>
    -<Value>
      <Name>status</Name>
      <Value>1</Value>
      <Name>code</Name>
      <Value>-2147467259</Value>
      <Name>source</Name>
      <Value>Exception occured in Microsoft OLE DB Provider for ODBC Drivers: [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified in ADO Connection Open.vi->Write Event.vi->Digital Output Events 6501 - Dev4.vi->Digital Output Events 6501 - Dev4.vi.ProxyCaller</Value>
    </Value>
  </Terminal>
  -<Terminal>
    <Name>value</Name>
    <Value>Status=0&Line=0&Port=0</Value>
  </Terminal>
</Response>

The VI's I'm running are quite simple:

1) Digital Outputs Events 6501 - Dev4.vi

2) Write Event.vi (this is the "EVENTS" sub-VI)

I'm running labView in a 64 bit Windows 8.1 system

My question is simple. ¿Why does the ADO Open Connection task work well if I run Digital Outputs Events 6501 - Dev4.vi manually from the front panel or block diagram, but the task doesn't work when I call the web service from my browser?

Thanks for your help

[aputman]

The error code says that it can't locate the DSN (Trasterox).  Have you tried using just a connection string rather than pointing it to a DSN?  I am not familiar with web services. 

[ArturoSH]

I found the reason it wasn't working.

I defined the DSN in the "user DSN" tab but not in "system DSN" tab. "User DSN" tab definitions work well when exceuting the VI from LabVIEW or a .EXE application or even from the web service debugging method URL, but when the VI is executed from a web service, the ODBC connections defined in the "user DSN" tab cannot be accessed by the web service. So the solution was simple: just make sure to define the ODBC connections in the "system DSN" tab.

Thanks for your help anyway