现实是其它的电脑，包括 mac os 也可以访问。唯独 android 不行，试了 n 个客户端也连接不上。好一通 google 最后找到这篇贴子

http://www.tomshardware.com/answers/id-2165494/connect-win7-share-android-fine-windows-machines.html

根据 pgammelby 的方法成功解决：

I had the same problem and fixed it by reenabling the SMB protocol as described here: http://support.microsoft.com/kb/2696547? To enable or disable SMB protocols on an SMB Server that is runningWindows 7, Windows Server 2008 R2, Windows Vista, or Windows Server 2008, use Windows PowerShell or Registry Editor. (Search ‘powershell’, run it in administrator mode) paste the following cmdlet into the powershell: Set-ItemProperty -Path “HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters” SMB2 -Type DWORD -Value 1 -Force and hit enter. Reboot. Worked like a charm.

照看是启用了 smb2 协议。