Not much to contribute other than a suggestion that the salesman in question problem isn't going to make a lot of friends by bloating his emails with graphics files...
![[lol] [lol] [lol]](/data/assets/smilies/lol.gif)
Here's one fix I've tried with success in the past:
"Choose Tools | Options | Mail Format.
Make sure the default format is set to HTML.
Click Signature Picker.
On the Signature Picker dialog, select the signature, then click Edit.
On the Edit Signature dialog, click Advanced Edit. This will open the .htm file for the signature in your system's default HTML editor.
Use your HTML editor's tools to insert a graphic.
Save the file and click OK until you return to Outlook.
If you don't have an HTML editor, you can locate the .htm file for the signature in your Windows\Application Data\Microsoft\Signatures folder, then edit it in Notepad to add an HTML image tag like this:
<img border="0" src="file:///Driveletter:/picture.gif">
You can also use either of these techniques to add other HTML tags to your signature -- to play sounds, run marquees and generally make a signature so busy and junky that people stop reading your mail."