Here's some information from Word MVP Jonathan Wood:
"Microsoft makes an ActiveX DLL available called dsofile.dll, which allows you to read and write the document properties of an Office file without opening the file in a document editing window."
"The download includes the DLL itself, plus the source code for a small VB5/VB6 project that demonstrates its use. While the VB code can't be used unmodified in VBA, looking at it should give you a pretty good idea of how to use the DLL."
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