In an effort to streamline our focus on the best photo experience, we have discontinued support for video uploads. Please note that you can still view your videos in your account even though this feature is no longer available.
Is your video not playing?
Make sure you have Adobe Flash installed and that it's updated: http://get.adobe.com/flashplayer/
Add-ons and extensions can also affect your browsing experience. Most add-ons require that you give your permission before they are installed, however, some may be installed automatically: You may want to disable them to see if that solves the problem: Could add-ons be affecting my browsing experience?