To Disable SMB2 and OPLOCK (Network Locking Errors)

To be done on all computers on the Network by a User with Administrator rights.

Users with Windows 10 build 16215 and Windows Server 2019 can use SMB3 Leasing Mode

If it has already been done you will see a file names SMB2 sitting under Parameters with a value of 0 (zero)

To disable SMB2.0:

   1. Click Start, type regedit in the Start Search box

   2. Locate and then click the following registry subkey:

      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters

   3. On the Edit menu, point to New, and then click DWORD Value.

   4. Type SMB2, and then press ENTER.

   5. On the Edit menu, click Modify.

   6. Type 0 (zero), and then click OK.

   7. Exit Registry Editor.

   8. Restart the computer.

Disable using Powershell

Search for POWERSHELL in the start menu.

Right Click and Run as Administrator

In the prompt that opens paste in the following commands one line at a time:

The first disables SMB2, the 2^nd enables SMB1

Set-SmbServerConfiguration –EnableSMB2Protocol $false

Set-SmbServerConfiguration -EnableSMB1Protocol $true

Restart the computer.

Once this is done, check that the Dialect is below 2 by running this command in Powershell as Administrator

Get-smbconnection

**An option but unconfirmed  **

Also check the Windows features, ensure the Automatic Removal is off. 

Configuring opportunistic locking in Windows

http://support.microsoft.com/default.aspx?scid=kb;en-us;296264

You can disable opportunistic locking by setting the following registry entry to 1:

OPLOCKS

To disable Opportunistic Locking:

The location of the client registry entry for opportunistic locking varies depending on the

version of Windows, so you will have to follow instructions from either point 2 or point 3 below:

 Click Start, type regedit in the Start Search box, and then press ENTER.

1. Locate and then click the following registry subkey (*If there is no Parameters folder under

MRXSMB, go to point 3):

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MRXSmb\Parameters\*

1. On the Edit menu, point to New, and then click DWORD Value.
2. Type OplocksDisabled, and then press ENTER.
3. On the Edit menu, click Modify.
4. Type 1 (one), and then click OK.

OR:

3. Locate and then click the following registry subkey:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters

1. On the Edit menu, point to New, and then click DWORD Value.
2. Type EnableOplocks, and then press ENTER.
3. On the Edit menu, click Modify.
4. Type 0 (zero), and then click OK.

 After both SMB2 and OPLOCKs have been disabled:

1. Exit Registry Editor.
2. Restart the computer.