OpenVPN: Windows 7 x64 client cannot see remote LAN, but XP client can
Solution 1:
Well i faced the same problem. Tried all the stuff like enable file sharing, setting same workgroup, etc. Nothing helped but this:
I noticed that there is a multiple number of network adapters in Device manager. All were hidden so one must click View and enable hidden devices.
All of them were named something like ...4to6 adapter. When I removed all these adapters my file/printer sharing and networking with XP clients starts working after reboot. If there is a huge number of these adapters you have to remove it all. It can be done using appropriate (32 or 64 bit version) tool DEVCON.EXE (which is part of Windows Driver Kit - Download details: Windows Driver Kit Version 7.1.0). More can be found here The DevCon command-line utility functions as an alternative to Device Manager.
I found this solution here: http://ryanvictory.com/posts/automating-6to4-adapter-removal-in-windows/