wbbatch fail once and on re-execution it executed okay

Hi,

We have script to build workbooks automatically. wbbatch RPAS utility is used for that. This batch is ending not okay with the below error.

Cancelwizard exception: Pre-range masking resulted in an empty set for '%1' wizard. Workbook cannot be built

I understand that there is problem in the wizard selection (selection file might be empty for one of the wizard).

Now, I have three questions around this:

1. Can we check through utility or Is there any other way to check selection file?

2. Second, post one execution this batch was re-executed without doing anything and this batch completed okay, which is quite strange. What could possibly the cause of this?