The error is caused by OS X trying to save metadata for copied files in resource forks (NT terminology) / named streams (Mac terminology). If the server (usually Samba) doesn’t support this it can be disabled
1. For a Mac user, when connecting to any SMB server, write
[default]
streams=no
in ~/Library/Preferences/nsmb.conf

2. For all Mac users, when connecting to a specific share
touch "/shared dir/.com.apple.smb.streams.off"
while there, you should also do a
touch "/shared dir/.metadata_never_index"
3. Samba can also disable the forks and extended attributes for all clients, use
[global]
ea support = no
unix extensions = no
in /etc/smb.conf