Initialize the shift register on the For loop. When it is uninitialized it retains it's last value which is why you are seeing your string building each execution.
Mark Yedinak Certified LabVIEW Architect LabVIEW Champion
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You have an uninitialized Shift Register. So it will keep what was last stored in the Shift Register.
However, you don't even need that loop. There is a lot of simplification we can do here.
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