Never, I repeat, never agree to present anything using any web tool without first practicing your delivery and testing the tool's capabilities.
Granted, I have used Webex hundreds of times. But apparently the folks who asked me to present today had experienced problems with their solution before and there was a conflict with PowerPoint 2007. So you need to test your particular slide configuration with their particular Webex configuration, phone lines etc. Don't ever assume it will work.
I can only offer my heartfelt apologies to the poor attendees who had to suffer through the missing visuals that were the key to my entire presentation today. And the worst part is, they did get to see the first two slides, one with the title and my name and the second with my bio, website link and photo. No way those people are going to forget the lousy presenter they saw today.
That's how we learn, and no matter how smart and professional you think you are or how many books you have written and blogs you have authored, there is absolutely no substitute for good preparation, planning and practice.
Shame on me.