This article was previously published under Q224287
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IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:
256986 Description of the Microsoft Windows Registry
When you attempt to connect to a third-party SMB server, such as DEC Pathworks or Samba, you may receive the following error message:
System error 1240 has occurred.
The account is not authorized to login from this station.
This issue can occur if the non-Microsoft SMB server supports only unencrypted (plain text) passwords during authentication.
To resolve this issue, contact the third-party SMB server manufacturer.
To work around this issue, use Regedit to enable unencrypted (plain text) passwords for the SMB client.
WARNING: When you enable unencrypted passwords, you allow unencrypted (plain text) passwords to be sent across the network when you authenticate to an SMB server that requests this option. Anyone using a packet monitoring utility on your network, such as Network Monitor, can read your password by taking a trace of network traffic.
WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
To enable unencrypted passwords, add the following value and data value to the following registry key:
Value Name: EnablePlainTextPassword Data Type: REG_DWORD Data: 1
For additional information about this issue as it applies to Microsoft Windows NT 4.0 SP3 or later, see the following article in the Microsoft Knowledge Base:
166730 With Unencrypted Password SP3 Fails to Connect to SMB Server
Beginning with Microsoft Windows NT 4.0 Service Pack 3, the SMB redirector does not send an unencrypted password during authentication to an SMB server unless you add the registry entry described in this article.
In earlier versions of Windows NT 4.0, the client automatically negotiates unencrypted (plain text) password authentication if the server requests it.
plain text enableplaintextpassword password samba smb