LabVIEW Error -1073807303

[EFM]

Recently, after many months of successful operation, my LabVIEW 5.0 application is tending to crash after about 12 hours of operation, returning error code
-1073807303 which is not listed in the internal database. Can anyone tell me what this error is and what may be causing it? My application runs GPIB communication with Agilent hardware about once every 5 seconds. In the past I have run this program for over 3 weeks non-stop.

[crelf]

If you upgrade to at least 6.1, there's a nifty way of finding out what errors mean: all you need to do is right click on an active error cluster, and select "Explain Warning/Error". I got:

Warning -1073807303 occurred at an unidentified location.
Possible reasons:
VISA: (Hex 0xBFFF0039) Unable to queue the asynchronous operation because there is already an operation in progress.

I hope that gives you something to go on!

cheers,
Christopher

[EFM]

Thanks for the code. You can right click and get explain error in LabVIEW 5.0 too, its just that particular code was not listed in the database. I suspect the extended error database is the difference between 5.0 and 6.1

This problem began occurring about a week after I installed some freeware called "TightVNC" on the machine. This freeware allows you to log in and remotely view/control the desktop of the machine. Since I uninstalled the freeware the problem seems to have disappeared, although it's early days yet.

[crelf]

Isn't that odd?! I must admit that I use regular VNC (not the Tight version), and have never had any probelms - I wonder if the TVNC server app was loading down the CPU?

[EFM]

That's my theory - since I uninstalled, the problem hasn't re-occurred, touch wood. Its strange though; the problem only started a couple of weeks after I installed & commenced using TVNC. And it never crashed when I was remotely viewing it. I only thought of it as being the cause when the crashes became more frequent as I logged on more frequently.