1) Press “Windows Key + R” and Type “Firewall.cpl” and Press Enter.
2) Microsoft Windows Firewall Window will Open. 3) Tap On “Turn Windows Firewall on or off”
Note: You will need Administrator rights to disable firewall.
4) Under “Home or Work Network Location Settings” And “Public Network Location Settings” Click On “Turn Off Windows Firewall”
Warning: You can activate Microsoft Windows Firewall after Office 365 repair is complete.
Step 2: Check Proxy Setting
1) Open Control Panel. Windows 7 : Press Win Key and then Select Control Panel from Right window. Microsoft Windows 8 : Press Windows Key + Q and Type “Control” And Click on it. 2) Open “Internet Options” In Control Panel . 3) Select Connections Tab and then Click On LAN Setting.
4) Turn off “Use a proxy server for your LAN” if its already ON.
Step 3: Check System Integrity
1) Press Win + R
2) Type cmd and Press Enter.
3) Type “sfc /scannow” and press enter.
Step 3:Check System Files For Error
1) Press Windows + R
2) Type Cleanmgr and Press Enter.
3) Select the OS Partition and Press OK. 4) Finally Click on “Clean up System Files”
Step 4: Try the installation again
In most case 30045-27 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.