Paste the 4 lines of text below into a .txt file (via Notepad) and rename it so the extension is .bat instead of .txt (eg. “Disable SMB2.bat”). Right click on the .bat file and select “Run as Administrator” and then restart your PC when complete.

title Disable SMB 2.0
sc config lanmanworkstation depend= bowser/mrxsmb10/nsi
sc config mrxsmb20 start= disabled
pause

If you decide you want to re-enable SMB2, follow the same steps but copy and paste the commands below into a .txt file and rename it to a .bat file:

title Enable SMB 2.0
sc config lanmanworkstation depend= bowser/mrxsmb10/mrxsmb20/nsi
sc config mrxsmb20 start= auto
pause

Excel Slow to open on network drive.

Fix:

Disable SMB 2.0.

You need to apply the fix (below) to both the “client” and the “server” operating systems.

Client

To disable SMB 2.0 for Windows Vista, Windows 7 or Windows systems that are the “client” systems run the following two commands:

sc config lanmanworkstation depend= bowser/mrxsmb10/nsi
sc config mrxsmb20 start= disabled

Note there's an extra “ ” (space) after the “=” sign.

Server

Run “regedit” on Windows Server 2008 based computer.

Expand and locate the sub tree as follows.

HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters

Add a new REG_DWORD key with the name of “Smb2” (without quotation mark)

Value name: Smb2

Value type: REG_DWORD

0 = disabled

Set the value to 0 to disable SMB 2.0.

Reboot the server.

Issue is fixed