1) Press “Win + R” and Type “Firewall.cpl” and Press Enter.
2) Microsoft Windows 8 Firewall Window will Open.
3) Click On “Turn Windows Firewall on or off”
Warning: You will need Admin privileges to disable firewall.
4) Press Turn off Windows Firewall (not recommended) under each network location and then Click “OK”
Step 2: Temporarily turn off Proxy Settings
1) Goto Control Panel. Microsoft Windows 7 : Press Win Key and then Click On Control Panel from Right Pane. Microsoft Windows 8 : Press Windows Key + Q and Type “Control” And Click on it. 2) In Control Panel Click on “Internet Options”. 3) Click On Connections Tab and then Click On LAN Setting.
4) Uncheck “Use a proxy server for your LAN” if its switched ON.
Step 3: Repair System Files
1) Press Win + R
2) Type cmd and Press Enter.
3) Type “sfc /scannow” and press enter.
Note: You will need Admin rights to run the sfc command.
Step 4: Try the installation again
In most case 2-4-0 error code in Office 365 should be resolved by now, if however the problem still persists please get your system checked by an expert.
If you are not able to resolve the issue following above steps, you can contact our 24×7 Chat Support for help.