Windows 10: How to Change PDF file icon to another icon

I have a Lenovo Ideapad S340 Laptop running Windows 10 and Microsoft programs. I downloaded the Lenovo User Guide for the S340. The icon for the user guide is PDF. I want to change this icon from PDF to Lenovo. I found the Lenovo icon in ico form and downloaded it to my computer. After removing the check mark from hidden files, I went to folder options, then my pc, found the user guide file with the pdf icon, clicked on it, when it opened I clicked on view, change icon, browsed back to downloaded icon and clicked on it. It appeared, so I clicked ok, then apply and ok again. But the icon Lenovo failed to replace the PDF icon. Can someone guide me?

:)

 

Appended icon in some files in Win7

Looks like this whole icon thing was some kind of explorer.exe bug ,the icon changed to a Diablo 3 icon , after another reboot, it changed back to the windows media "play" icon.

Nevermind ... I remember this bug elsewhere in another situation, happens sometimes when a lot of icons get randomly choosen instead of the correct one.

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Win7 always has something to confuse the heck out of you.

 

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added html code to suggest the icon to browsers

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Suggestion to have an option to change Notification Area icon this way too.
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