Captivate outputs (generally) as Flash. So as long as users have a recent version of the Flash player, they should technically be able to play back the content.
However, of course, online delivery depends on the user's internet connection. What if you're feeding them video and their connection is slow?
For similar concerns, we point our users to speedtest.net and ask them to post their results. Sometimes that helps illustrate their slow connection means a slow video delivery.
And, of course, the older the computer, the less-fast it'll be in rendering the course. My oldest computer, used occasionally and with frustration by my 5 y/old, plays Flash sites horribly - and it's a 1.6ghz computer with 512mb RAM and XP...with latest browsers and Flash player. You can always ask for their computer spec, but that's not an easy thing to determine via software/website.
So you can create a simple 'minimum requirements' page that you can point to...but one that actually does a diagnostic...well, aside from simple Flash player/version detection (which is fairly simple), that's a complex task.
Thanks for your input. True to all your comments. It's at a university, and the pipe is pretty fast. True that some PCs are running XP, but many, if not most, are Win 7 (or Mac OS X). The content is streaming, so why it would have problems ONLY at a video is strange. I agree it would be helpful to list minimum standards for online delivery, which we do for Blackboard. I do love the diagnostics Adobe has for Flash, and the "test" for Connect. Maybe I should just create a very basic page test page that incororates the Flash test, displays their browser name and version, and speed. Then they could provide the info if they have problems to see if there is a common thread. Thanks again!
"why it would have problems ONLY at a video is strange"
Other slides are going to be pretty quick to load, even on a slower connection, being text and images. Video, on the other hand (as you likely know) is a lot more intensive - several 'frames per second' of images trying to load quickly. And unless you've got an actual 'streaming server' in the backend, it's just progressive streaming like the rest of the content.
So one idea may be to use video with a lower frame rate?
Or, what exactly is the problem? It's not that some users don't see the video at all...is it? It's that it comes in slow and/or choppy....? Which indicates a bandwidth, or possibly rendering, or both, issue.
But overall I agree with your idea - such a diagnostic page sure couldn't hurt!
Good call. Works sometimes and not others on the same computer? Either a delivery problem or a computer-resource problem almost surely. If the net connection seems fairly stable and unsaturated, then get the specs of the computer and be sure it's not overwhelmed.
Trying to do a Flash piece with video on an older computer with minimal CPU/RAM and perhaps a few other applications open and running...could result in some poor playback.