The primary Windows registry setting for accessing a Samba share is AllowInsecureGuestAuth and should be found in the windows registry for each machine as per the key details below.
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Allow insecure guest authentication
This setting is often needed for Samba shares that don't require a password.
Registry Key: HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\LanmanWorkstation
Value Name: AllowInsecureGuestAuth
Type: REG_DWORD
Value: 1 (to enable)
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