Hi LHa,
After creating some dummy PDF files and changing the path inputs to point to my system, the code generated the combined PDF without error.
Can you provide a detailed description of the list of steps you perform to generate that error? The steps I followed were:
1) Run the VI
2) Select an item from the "QDTE Ref No" dropdown
3) Select an item from the "Submission No" dropdown
4) Select "Final Report" in the unlabeled top dropdown
5) Click the "View Report" button
Since I can't reproduce the error, it would also help if you could identify exactly where the error originates from using some combination of highlight execution, probes, and breakpoints (LabVIEW Debugging Tools). The error you reported appears to be generated from an invoke node, but when I search your VI (ctrl+F) for invoke nodes, I don't find any, which is curious.
As general feedback, I would recommend ensuring your error handling is complete, combining your different events into a single event structure, moving your controls into the event case that handles them to ensure they are read and reset properly, and adding a stop case to the combined event structure so the code stops when commanded(modified code is attached).
You might check on your file permissions, as well. That seems to be the most salient difference between our cases. I created some dummy PDFs and didn't get the same error, so you may just have some or all of them set to read-only or something of that nature.
You might also want to contact Simplicity if you haven't already. The error you reported doesn't give much information, but they may have some useful input.
Regards,
