Can not access computer on Windows network (0x80070035 The network path was not found)

Computer "A" and "B": Win 7 Ultimate x64, Kaspersky Internet Security 2015, Windows Firewall turned off, UAC turned off, users are Admins.
Asus RT-N12D1 WiFi router: Firewall and DoS protection turned off.
"A" & "B" ping each other and itself. Networks are Home type.
Network Discovery, File Sharing — on.
"A" is connected to the router via cable.
"B" — via WiFi.
"A" & "B" are visible in the networks of each other.
"Limit local account use of blank passwords to console logon only" — disabled.
I can access "A" from "B".
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Edit:
I uninstalled 6to4 Adapter from "A" (there was none on "B"). This didn't helped.

The problem: I can not access "B" from "A". (0x80070035 The network path was not found)

I had TCP/IP NetBIOS Helper disabled on "A". So re-enabling it solved the problem.