Thanking to this answer http://superuser.com/a/704697/200806 I discovered ADS (Alternate Data Streams) and started to play some demo: created a test.txt:hidden file with hidden in ADS content. I can see from the same PC where I created it, but when I am copying it over network - hidden content is lost.
Both PC are on Win7x64, target drives are NTFS, connected via Team Viewer VPN (tried both RDP and Share copying - result the same: hidden content is lost)
Is ADS content persistent when copying over network in generally? If Yes Why in my case content may be lost?