I have 2 win7 machines and 2 xp machines. Networking is setup with no username and password. The computers can always access each others shared drives - there's no problems there. I have an android tablet (wifi), and a media player (ethernet connection) that is also android based. Once in awhile I will loose the ability to play things off my windows 7 shared drives because it will ask me for the user/pass to access them, but I don't have any password setup. It's very annoying, and I'm not able to find the right google search to find a solution to my problem. For them to access the shares again usually I'll have to restart my router and win 7 computer, but sometimes it will just fix itself (I'll go back an hour later and try to access it again and it will work just fine). It has never stopped in the middle of a movie and asked me for the user/pass, but sometimes if I stop the video for just a second it will freeze me out and ask for the user/pass. FYI - I'm using File Manager HD and ES File Explorer on my media center and tablet - when this happens neither app will allow access to the shared drives.