Did the exact same thing work previously on your machine and then it suddenly stopped working?
If that's the case, first I'll just say that it sounds about right when dealing with automating any Microsoft Office product (through interop). The fact that it works on another PC (I assume in the same Blue Prism environment), then it likely has to do with the Office installation on your machine. I'd be curious to know if the other machine starts showing the same issues at some point which could mean some Windows update that hadn't yet been pushed to the other machine yet. But for sure the first thing I'd try is uninstalling and reinstalling Office.
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Dave Morris
Cano Ai
Atlanta, GA
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Dave Morris, 3Ci at Southern Company