One of my clients received a new 2012 R2 server, with over 10tb of drive space on the data drive.
During the process of migrating their data from the old 2003 R2 server, I ran into the error message "Not enough server storage is available to process this command" while just manually copying the files through Windows Explorer. There was approximately 1tb worth of data to copy. Giving me 9tb free on the drive. Plenty of space.
The files were of random sizes. Some being 50gb in size, others being 10mb in size. There was no rhyme or reason.
Out of curiosity I decided to utilise Robocopy to complete the task. I normally use this for data to retain permissions, but had neglected to as this was just a backup repository.
I ran the following command robocopy \\sourceserver\folder e:\folder /mir /e /log:log.txt
All the files copied successfully.
Moral of the story? Always use robocopy.