Thnak you for reporting the problem.
Indeed this is the second time such issue appears, and we're currently investigating the possible causes of the problem with highest priority.
Unfortunately currently we're not able to provide an alternative link to the item, please excuse us for the inconvenience caused by this downtime. Alternatively you could try loading the cached version of the page:
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items