Can't open office 2003 .mdi files using Office 2007

I recently saved a whole load of tutorials in MS Office's .mdi format using 2003 so as to save some trees :) I was quite surprised when I loaded these files onto my machine with office 2007 because they could not be opened. Now Office 2007's electronic format is in .xps so I knew I had a problem. Quick search on google turns up an MS KB article to solve the problem:-

1. Click Start, click Run, type appwiz.cpl, and then click OK.
2. In the Currently installed programs list, click the 2007 Office version that you have installed.
3. Click Change.
4. Click Add or Remove features, and then click Continue.
5. Expand Office Tools.
6. Click Microsoft Office Document Imaging, and then click Run all from My Computer.
7. Click Continue.

Ref: An .mdi file does not open in the Microsoft Office Document Imaging program that is included in the 2007 Office programs