Send to Network Folder does not work when connecting to a folder on a Macintosh OS 10.7 (Lion) system.
Apple changed the way they communicate with the SMB protocol to make it more efficient and more secure.
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Inside Mac OS X 10.7 Lion Server: Apple replaces Samba for Windows networking services
The release of Mac OS X 10.7 Lion Server will remove the formerly bundled open source Samba software and replace it with Apple's own tools for Windows file sharing and network directory services.
Apple began bundling Samba with Mac OS X 10.2, enabling Mac users to connect to Microsoft's Windows file and network directory services based on SMB (Server Message Block, a protocol also known as Windows File Sharing).
In both Mac OS X Server and client editions, Samba enables Macs to share files with Windows clients on the network and access Windows file servers.
However, the Samba team has moved active development of the project to the more strict GPLv3 license, which prevents Apple from realistically using the software commercially.
Developers report that Apple has internally officially announced that it will pull Samba from Mac OS X Lion and Lion Server, and replace it with Windows networking software developed by Apple. The new replacement for Samba is said to be named SMBX, and supports Microsoft's newer SMB2 version of its proprietary but openly published protocol, which was originally released in Windows Vista.
While Mac OS X's previous Samba only supported the original SMB1, Microsoft's new SBM2 is both faster and more efficient, reducing the number of commands and subcommands from over a hundred to just 19, while adding pipelining of commands (to more efficiently transact over slow links), support for symbolic links, caching of file properties, and larger storage fields supporting better performance of large file transfers over fast networks.
Apple's Windows file sharing software in Lion will continue to allow Macs to both provide and access Windows-style file shares, but reportedly will not support the NT Domain Controller features of Samba, which relate to Microsoft's 1990's, NT-era directory service supported prior to Active Directory, which was released alongside Windows 2000.