See if http://www.berezniker.com/content/pages/visual-foxpro/changing-windows-default-printer helps

>I'm creating an app where existing PDF files will print based on sales data. The PDF files are already created and sitting in a folder on the network. I'm using ShellExecute to print the PDFs, and need them to print to a specific printer which isn't likely to be the user's default printer.
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>I found the code to change the default printer using WMI (Thanks Sergey!) but the problem is that ShellExecute doesn't recognize that change and still sends the PDF to the original default printer. I tried creating a separate EXE that gets called from the first program that changes the default printer but that didn't work either (throwing darts at this point).
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