I've recently had a problem with ALL of my Android devices not seeing my Win 7 shares after upgrading my home server from XP (on XP they all managed to see them fine using ES File on the devices, for years) - all clean installs and shares all defo setup correctly but no matter what i did all the android devices would either keep asking for a password or just keep spinning. After a few attempts at rebuilds using both 32/64bit versions of Win 7 and alternative android apps with varying success I tried a fresh install with NO MS updates installed - magically everything worked fine. Installed my BitDefender suite - still all OK for days. Then ran the MS updates until they were all done (200+ over a day or so) - shares all went dead again. So.... i was now pretty confident that in my case it was an MS update that stops it working on my machine.