The first thing to try is refreshing the page with the video in it. Sometimes communications between your browser and servers can get interrupted, and a page refresh can fix this. If this doesn't work, or if you see an empty box where the video should be, go to step 2.
If the steps outlined above didn't help, please let us know by contacting us at support@techvalidate.com. Please let us know which browser and operating system you're using, and also which version of Flash you have installed.
Not sure which browser you're using? Visit whatbrowser.org to find out.