Having trouble viewing pdf (Using AcroPDF) when other user has it open

I can open a pdf over the network using AcroPDF, but i can not open a pdf if it is already open on another computer over the network. Are there sharing issues with AcroPDF?
I can open the same PDF on 2 computers using the Acrobat reader on its own.
this AcroPDF reader is version 7.

all i want to do is show spec sheets in my application. I'd rather not open acrobat as a separate application.

Thanks in advance.

Code:

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TheSpecSheet = rstSkuList!SpecSheet

AcroPDF1.Visible = True
AcroPDF1.Left = 100
AcroPDF1.Top = 1000
AcroPDF1.Width = SSTab1.Width - 300
AcroPDF1.Height = SSTab1.Height - 1500
Call AcroPDF1.LoadFile(TheSpecSheet)

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the browser control seems to work fine.

Code:

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WebBrowser1.Navigate2 "C:\Document.pdf"

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now i need to find a way to hide the PDF left side navigation pane to get more screen area.