I2048: NTLM authentication appears to be not working on WinXP
Summary
Product: FreeProxy
Versions: FreeProxy, 3.6 and above
Note: 2048
Date reported: 23 June 2004
Issue Detail
When authenticating to the WinXP local user base using NTLM, all accesses are allowed even though a non-existent user is being specified.
Solution
A registry entry in WinXP is normally set by default to authenticate all users as though they were guest users. According to the Microsoft technical note
the registry key HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlLsaForceGuest changes the behaviour of XP authenticator when authenticating to the local XP user database.
To ensure that FreeProxy always authenticates correctly, the ForceGuest registry value should be set to 0. In our experience, the influence of the Guest user being disabled or enabled has no effect on the outcome.
This registry setting does not effect authentication to a windows domain. For example, you have FreeProxy running on a WinXP system. Any authentication request that is received by FreeProxy for a user on the local computer is affected by the above registry setting. Any request received to authenticate a user on a windows domain is not affected by the above setting.