I am having trouble connecting from my work Win XP (Pro) desktop machine to a new work Win 7 (Enterprise) desktop to sync my work files to it. The XP PC can see my personal Win 7 (ultimate) PC that was upgraded from Vista Ultimate. Win 7 to Win 7 is ok. I have read and followed a lot of posts to no avail. Specifically I have followed the advice in "How to make Windows 7 work with older Windows versions for networking and file sharing" located here: How to make Windows 7 work with older Windows versions for networking and file sharing. - all machines are in the same workgroup - sometimes the work Win 7 PC doesn’t see the XP PC. - The work Win 7 network is defined as a 'home' network. Same for the other Win 7 PC. - I’m using the same user account with the same password on all PCs - firewalls are disabled on both boxes - Advanced Network settings - Network discovery in ON - File and Printer Sharing is ON - Public folder sharing is ON - password protected sharing is ON – I can’t save this to OFF. When I change it and go back, it’s on again. - Allow Windows to manage Homegroup connections - the shared D drive in Win 7 says its shared (its not in the public tree) - On folder Advanced setting security, 'Everyone' has been added & has full control permissions - On folder Advanced setting sharing it says "People must have a user account and password for this computer to access shared folders" I ran "regedit.exe", then went here: HKLM\System\CurrentControlSet\Control\Lsa\limitblankpassworduse and changed it from "1" to "0". The guest account password is blank. The guest account is off. In the security policy, -guest account is enabled -Network access: sharing and security model for local accounts, classic-local users authenticate as themselves Win 7 firewall is off. XP firewall-some settings set by group policy. File and print sharing is checked, group policy no. On the XP box the win7 machine appears in the Network list under the workgroup. I can see the shared D drive. When I click on the share, it says I might not have permissions to use this network resource.