Hi Coimbatore,
Unfortunately there isn't a lot of documenation on this error, but I suspect it means that the URL you are sending to the Datasocket Read is invalid. I would check that first. If you are not using a recent version of LabVIEW I would also suggest upgrading if possible as the error handling and Datasocket API have improved in newer versions of LabVIEW (currently at 8.2).
Doug M
Applications Engineer
National Instruments
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