First of all, log in the Freenas Console and check the file permissions (ls -la) on the guest folder. After that I think the problem is on the Windows 7 machine and the way to connect to CIFS folder, maybe is connected with the wrong username?
You'll need to provide more details - however off the top of my head you could try re-applying the settings for the Volume/Dataset and hit the "Set permissions recursively" checkbox.
You'll need to provide more details - however off the top of my head you could try re-applying the settings for the Volume/Dataset and hit the "Set permissions recursively" checkbox.
Cool. The GUI may have hung because it was recursing through all your files and updating the permission. Could take quite a while if you have a lot of files.