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Is there a way to add new file types to Windows explorer thumbnail view?

I have some files that are simply images with a non-standard extention (don't ask!) - is there any way to tell Explorer that these are really just jpegs and it should generate thumbnails as if they were jpegs?

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3 Answers 3

Okay, how about using Associate - you can download it here: http://www.vtaskstudio.com/support.php#tools it's tiny and portable.

Associate is a command-line utility for assigning file associations. 
This will allow you to double-click a file and have it 
load in the appropriate program. 
It also includes the ability to set a file type icon and startup parameters, 
and it automatically refreshes Explorer. Type "associate -?" for details. 

Syntax:       associate [extension] [program] 
Example:     associate .txt %WINDIR%\notepad.exe
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Click on Tools - Folder Options - File Types - Then click on New. In the extension box put the extension. Click on advanced, and then select "Jpeg Image" as the file type.

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Sorry for being dumb, I'm on win7 I don't have a File types in explorer. –  Martin Beckett Aug 11 '10 at 17:15
I suggested a different way below. I've tested it in XP, but I don't have a copy of Windows 7, I'm afraid. –  Doctor Trout Aug 30 '10 at 15:00

Sorry, didn't realise it was Windows 7.

Have to admit, I'm no Windows 7 expert. Could you write this in a text document, save it as "import.reg" and double click it to add it to the registry? It works in XP.

Just replace "YOUREXTENSION" with the extension you're trying to add?

Windows Registry Editor Version 5.00

"Content Type"="image/jpeg"


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Doesn't work on win7 unfortunately. Will post a solution when I find one –  Martin Beckett Sep 8 '10 at 15:10

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