I am also experiencing this behavior. Here are my stats:
Win 7 Pro.
IE 9 or Chrome (same error in both browsers).
I am the Stake Tech Specialist and am an admin.
In Building Reservations.
I am trying to edit a series that has the entire building reserved on the 1st and 3rd Friday and Saturdays for a Ward that meets in the building. Another Ward has the 2nd and 4th Friday and Saturdays (similar series). When I try to change the Entire building to specific rooms in the building that exclude the Family History Center and Primary room (the FHC uses the Primary room during the week), I get an error after clicking the Update Reservation button stating (it also asks if I want to update the entire series, which I do), "Message from webpage. Sorry, the data service has failed. Please contact support." Only option is to press Okay. I must press ESC to get the "busy" message to stop. Then I am back at my changed page, but am not able to save the changes I just made because it repeats the error. The work-around that I had to use was to delete the entire reservation and start over, which is annoying.