To share a folder on a Windows 7 machine you will need to allow for the files to be shared.
You can do this under “Network and Sharing Center” and then under “Advanced Sharing Center”.
So far, so good…
But if you don’t want users from the XP devices to get an popup asking for credentials, you will need to disable the “Password Protect Sharing”, again under “Advanced Sharing Center”.
My issue was that when I switched this setting from “On” (it’s default” to “Off” and saved it.
I still got a popup from the XP workstation, reboot did not help.
When I got back to take a look at the “Password Protect Sharing” setting I just changed, it was set back to “On” again! Whatever I did, it always came back to “On” again… I couldn’t let it stick to “Off”.
The cause and solution was fairly simple; the guest account on my Windows 7 machine was disabled… but also there was a password configured.