manually change pdf icon in windows 7

Customizing the Icon for a File Type
(For illustrative purposes, let’s assume that you have a custom file type .abc (for purposes of illustration) for which you want to change the icon.

1. Click Start, type Regedit.exe and press ENTER

2. Navigate to the following branch:

HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Explorer \ FileExts \ .abc \ UserChoice
3. In the right-pane, note down the value data for Progid (e.g. abcfile). This is the user chosen (via Default Programs) Programmatic Identifier for the file extension.

4. If the UserChoice branch does not exist, navigate to the following branch:

HKEY_CLASSES_ROOT \ .abc
5. In the right-pane, note down the (default) value data (e.g. abcfile). This is the Prog ID for the file extension.

6. Navigate to the following key (where abcfile is the Prog ID noted in Step 2 or Step 4 above):

HKEY_CLASSES_ROOT \ abcfile \ DefaultIcon
Note: If the DefaultIcon key does not exist by default, you need to create it manually.

7. In the right-pane, double-click (default) and mention the path to your custom icon (.ico file or reference to an icon resource from a EXE/DLL file).

Hint: You may use the icon picker dialog box to choose an icon from a EXE/DLL file. To launch the icon picker dialog, right-click on a folder in your system, click Properties. Click the Customize tab, and click Change Icon… button. Use the icon picker to choose the icon and make a note of the index. The index starts from "0" and you need to proceed vertically when counting (top to bottom.) Answered Jan, 31 2011