RestrictNullSessAccess

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters

Data type Range Default value

REG_DWORD

0 | 1

1

Description

Specifies whether the Server service limits access to the system by clients that are logged on to the system account without user name and password authentication.

Value Meaning

0

Null session access is not restricted. Unauthenticated users access all shared resources.

1

Null session access is restricted. Unauthenticated users can access only the server pipes listed in the value of the NullSessionPipes entry and the shared directories listed in the value of the NullSessionShares entry.

This entry does not exist in the registry by default. You can add it by using the registry editor Regedit.exe.