Rainald Taesler, one of OneNote's MVPs, had contacted me a while back asking to have the Table of Contents powertoy tweaked to show a button on the toolbar rather than a text string. The text strings tend to take up too much horizontal space on the toolbar and he wanted to replace it with his own image. Fortunately, there is a way to replace that command in the toolbar without writing code and only tweaking the registry. Here's how:

1. Exit OneNote.
2. First, create the image if you want to replace a string with an image. It needs to be a 16x16 BMP format image.
3. Save it in the same folder as the location into which you installed the addin. For instance, if you installed the addin to c:\program files\ microsoft\on table of content setup, copy your bitmap there. It doesn't really matter where you put it, just make note of where it is.
4. Now it gets a little tricky. Run regedit and open HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\OneNote\Addins
5. Highlight the addins key and right click it. Select "Export" and save the file to any location you want. This is now your backup in case the next few steps go awry.
6. You will see a bunch of GUIDS like {806AD7E…} and so on. For the table of contents addin, look for this GUID: {4FE3B6DF-28B8-41d0-A4F5-7010E236B4A2}. Expand its branch
7. On the right, you will see a string entry for "ButtonText" with a value of Table of Contents. Delete that key:

8.  Now add a new string value named "IconPath". For its value, enter the path you copied from step 2 and be sure to add the name of the image file. Here's what mine looked like:

9.  Click OK and exit regedit.  Like OneNote, there is no need to press a "Save" button :)

10.  Start OneNote. The "Table of Contents" button should be gone and replaced with the icon you created and pointed to!

You can also reverse these steps and make text strings show for any icons you want.

I followed the directions on page 11 of the "How to create toolbar addins for OneNote" PDF to come up with routine. Feel free to browse through it. You can even change which toolbar addin buttons appear on in addition to changing the icon. For instance, the task request addin I wrote for Outlook puts the icon for the addin on the Outlook toolbar (value == 9 in this case).

And if you want to change one of these values and get to step 4 and cannot find the addin you want to modify, be sure to look in HKEY_LOCAL_MACHINE instead of HKEY_CURRENT_USER. Some addins install their keys there so all users can get the same experience.

Have fun tweaking the addins for OneNote!

Questions, comments, concerns and criticisms always welcome,

John