Had this recently while deploying to Azure, to the blank staging slot of a cloud service that already had a production instance running.
Looking at the log, immediately before the error Visual Studio claimed that it was stopping a role – how can that be, when the staging slot’s already free? This is another situation where you shouldn’t believe Visual Studio’s lies – upload the package directly to the portal in the event of failure and you’ll generally get better and more accurate errors.
The issue in this case? We’d run out of spare cores in our subscription to deploy two medium instances of the application to staging. Why does the error talk about missing deployments (and try to stop non-existent deployments in this instance)? Unknown.