Adobe Reader v 7.0

Create a file called pdf.reg paste the code under the broken line into it, then right click on the file and select merge
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Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.pdf]
"Content Type"="application/pdf"
@="AcroExch.Document"

[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.pdf\OpenWithList]
@=""

[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.pdf\OpenWithList\AcroRd32.exe]
@=""

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Alternatively open an explorer window which can be achieved by double clicking in "My Computer" Once the window is open from the menu select "tools" from the resulting drop-down menu select "Folder Options...." A dialog box should appear select the tab "File Types" wait a little bit then you should see a long list of file types find "pdf" then click on the "Change" button, read all the options on the next dialog box carefully and you should be able to figure out from there how to make pdf's always associated with adobe reader 7.0

This is for Windows XP.
Right Click the start button and select Explore
From Explorer toolbar menu select the Tools then Folder Options
Select the File Types Tab in the Folder Options dialogue box
Scroll through the extensions until you get to PDF
Select PDF and in the lower box it should have Details for ?PDF? extension
Even if it says Opens with: Adobe Reader 7.0 click the Change button
In the Programs box make sure Adobe Reader 7.0 is selected and make sure the Always use the selected program to open this kind of file is ticked
Click OK to close the Open With dialogue box
Click OK to close the Folder Options dialogue box
Close Explorer and test file opens with Adobe Reader 7.0

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