Sudden Error -200077

Hi,

I have a measurement system thathas been running for some time that, without any apparent change to the hardware or pc that is running it, has begun giving an error: Error -200077.

It running with Labview 8.2.1, cDAQ9172, and a few modules

The full error discription is:

Error -200077 occurred at Property Node DAQmx Timing (arg 5) in DAQmx Timing (Sample Clock).vi:1->Instance          37  3PAI .vi->PAI.vi->wagu.vi

Possible reason(s):

Measurements: Requested value is not a supported value for this property.

Property: SampClk.Rate
You Have Requested:  0.000000
Valid Values Begin with:  22.250739e-309
Valid Values End with:  6.666667e6

Task Name: _unnamedTask<0>

Could it be a hardware failure, or a change to WindowsOS that could cause this?