Windows agents onv9.00 through v9.00 SP 11 and v10 through v10 SP 2 cannot determine free spacein the root directory of network shares for FileTransfers.
This was fixed inv10 SP 3.
1) Upgrade to V10 SP3, or greater.
2) As a workaround, youcan set ft_check_free_disk_space=N in the Windows agent's .INI file (globalsection).
3) Another possibility would be to change the destination path to asub-directory of the network share.