Cannot access Windows 7 shared folder from Linux box, logon failed

I have a media player box (Mvix Ultio) running embedded Linux.* It is supposed to be able to access shared folders in Windows.* It worked flawlessly with Windows Vista Ultimate.* However, it is unable to access shared folders on Windows 7 Ultimate machine.

From the Linux box, I could see the Windows 7 machine on the network.* Selecting the Win7 machine, it asks for user credential.* I put in the user credential of a user account created on the Win7 machine, as I successfully did with Vista before, it complains that logon failed.* So I cannot proceed to see the shared folders from Win7.* When accessing the Win7 machine from another Win7 machine belonging to the same workgroup, there is no problem.* When accessing the Win7 machine from a Vista machine that belongs to a different domain, but connected to the same home network, it asked for user credential.* I put in the same user credential as I did*on the Linux box (that of a user account on the Win7 machine), there is no problem.* I can access the Win7 shared resourced from the Vista machine.

My network is home network in workgroup mode.* The Linux box can logon to Vista machine connected to the same network, regardless of whether the Vista machine belongs to the same workgroup or a different domain.

Win7 Ultimate RTM settings:
Network discovery: turned on
File and printer sharing: turned on
Public folder sharing: turned on
Media streaming: off
File sharing connection: tried both 128-bit encryption*and 40- or 56- bit.* Both not working
Password protected sharing: tried both enabled and disabled.* Both not working
HomeGroup connections: allow Windows to manage.* Also tried to disable HomeGroup completely (by stopping and disabling both the HomeGroup client and server services), still doesn't work.* (I now keep those services disabled since it otherwise completely messed up with access rights I setup for different folders that I want other people to have, locally and remotely.)

Shared folders on the Win7 machine give Everyone read access.

Tried the method described in http://www.tweaktown.com/news/13274/...s_7/index.html.* Still no go.

Tried enabling network security auditing, etc, no entries were found in event logs.

Please advise what I did wrong or where else I should be looking at.

Thanks.

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