How to remove McAfee in Windows 7

Our company used McAfee but it's not able to be uninstalled.

The strategy is to use safe model, but by default windows installer service is not started in safe model. The ways to solve it:

A.
Safe Mode.
Type this in a command prompt:
REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal\MSIServer" /VE /T REG_SZ /F /D "Service"

and then

net start msiserver

This will start the Windows Installer Service.

Safe Mode with Network
REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Network\MSIServer" /VE /T REG_SZ /F /D "Service"

and followed by

net start msiserver

B. stop service as possible as you can, disable all McAfee related services
C.
Step 1: Find where the FrmInst.exe file is located. Generally located in C:\program Files\McAfee\Common Framework
Step 2: Open command prompt.
Step 3: Run this command: C:\program Files\McAfee\Common Framework\frminst /forceuninstall