I have three computers all running Windows 7 Ultimate x64, one of which functions partly as a media center (hosting music etc), the second and third being my office workstation and laptop respectively. The media center has a hard line to my cable modem (via Trendnet wireless-N router) while the latter two connect via wireless; the workstation via a wireless ethernet hub and the laptop via it's integrated wireless. I currently have all of my media folders shared via homegroup on the media center. My laptop (Lenovo Thinkpad W500) can access all of the shared folders. I have a wireless printer that all three computers (media center, workstation, and laptop) can connect (and print) to with no problems. My office workstation, while I can "see" the shared libraries and folders on my media center, hangs (the explorer window appears to be perpetually loading) whenever I attempt to open any of the folders. Sometimes when this happens I can kill/restart explorer but ever so often explorer itself will be unable to restart and I will have to reboot the entire machine. Usually after attempting (and failing) to access a homegroup folder (and subsequently restarting explorer) I will no longer be able to see the shared libraries or folders on my media center. I have Windows Security Essentials running on both machines - all three are almost identical with respects to the installed software. I have tried reconfiguring the homegroup multiple times, flushing the dns cache, resetting and cycling the router, and have even swapped out wireless adapters (on the problematic workstation) to no avail. Any advice would be much appreciated!