Download and install the Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats. The URL is here.
Please try the 3 ways below:
1. Recommend your colleague download the MS Compatibility Pack for Office 2007, it free to use. Just install it on its computer, you can view the 2007 presentation with no difficulty.
2. Transfer your PowerPoint presentation to Flash.
Using some 3rd party presentation to transfer your presentation to Flash presentation from PowerPoint.
3. Upload your presentation to Slideshare, then your colleague can view the presentation online.