Mine was caused by name collision between two processes both using instances of the DTS "Copy SQL Server Objects Task" component. It scripts objects to the folder mentioned above, and in my case collided intermittantly on the "<servername>.<dbname>.DP1 or .DP2 files, which it generated identically for two logic branches (one doing schema-only objects, the other doing data-copy). I changed the step-dependency to serialize those steps, and the problem went away. It's a design issue IMHO; the DTS-generated filenames of the parallel processes could have included a guid.