I've run into those from time to time and that's really the only problem I've had with Internet browsing. And the decision to go with Active X in my opinion is a disaster anyway: so many other/better technologies, browser incompatibility even from one version of IE to another...
The one thing you did was vote with your feet and move on. Good for you. Question is did you tell the company that you were disappointed with them?
Other one I've occasionally run into is Adobe Acrobat version issues or Flash issues, but again you run into the same issues.
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