Hi @SoulStrider12345 ,
Which version of Office is your client using? And yours?
I suggest you create a new Excel workbook on your local machine, then insert objects (Such as Word document, PDF files) and open them for a test.
I would also suggest the PDF reader on your machine and the PDF editor on clients' machine should be from the same software development company.
> All the files are embedded inside the excel document, they are not links to external documents.
Do you mean those object are displayed as icon, the "Link to file" is not ticked when inserting?
It's recommended to disable protected view temporarily.
If there is any security software, it is recommended to temporarily quit it.
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