1) Click Start Button and in search box type Control Panel and Click on it.
2) In Control Panel , Open Windows Firewall.
3) Press “Turn Windows Firewall on or off”
Note: If you are logged in as Normal user you may be asked to login as Administrator.
4) Click on “Turn off Windows Firewall (not recommended)” under each of the active network connections.
Note: You can activate Windows Firewall after Office 365 installation is complete.
Step 2: Temporarily turn off Proxy Settings
1) Goto Control Panel. Windows 7 : Click On Start and then Select Control Panel from Right Pane. Microsoft Windows 8 : Press Windows Key + Q and Type “Control” And Click on it. 2) In Search Box Type Internet and 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 already 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 Administrator rights to run the command.
Step 4: Try the installation again
In most case 3008-27 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.