The package validates, then fails because it's not allowed to create the file c:\checkpoint.XML (Windows 7).

No checkpoint file was specified and I can't find where the checkpoint is. There's only one control-flow task, and neither the package itself or that task seems to have one.

In the light of day, turning off checkpointing in the Package Properties cured the problem. The 3 settings, CheckpointFileName, CheckpointUsage (Never) and SaveCheckpoint (false).