Downloading PDF From outlook.com Changes Name Of File

Thank you for the response.

No, "my workbook" is not a default name. The default name for an Excel file is Book1, or Book2 if Book1 is currently open, or Book3 if Book2 is currently open, etc.

"My_Workbook.xlsx" and "My_pdf_Workbook.pdf" were just example names for the purpose of my question. The bottom line is whatever filename I use to save the .xlsx file is the name that is somehow picked up by office.com, along with "- document.pdf" appended to it. However, when I save the document to my PC or Chromebook, office.com drops the filename.xlsx portion and saves it as document.pdf. If document.pdf already exists in the download folder, it saves it as document (1).pdf, etc. The filename that I give the xlsx file when I convert it to a pdf is completely ignored.

gmail picks up the pdf filename and Outlook 2013 (within Office 2013) picks up the pdf filename. It's only Outlook.com that uses the original Excel filename, including the .xlsx extension, and then adds "- document.pdf" when it displays the pdf but then drops the xlsx filename when it saves it. 

It's all very strange.