-> Connect your Xiaomi MI2 or MI2s with the computer.
->Open the drive named Xiaomi in Mycomputer.
->Find the file named setup.exe inside the Xiaomi drive.
->Right click the file to select properties.
->Click compatibility Tab in the setup Properties.
->Check "Run this program in compatibility mode for", select your windows version which is Windows 2000 in case of Windows XP.
->Click apply and OK.
->Run the setup.exe file in the Xiaomi drive.
->Go with yes, next, OK to setup. Even if it is in Chinese, it is easy for you to select those.
->Click continue anyway if asked.
->Click install automatically if you are asked for the setup.
->Your Xiaomi phone will be connected after successful installation of the driver.
Now you can easily access the files in the phone from the Mi2 drive in My Computer.
Though the above procedure works for MI2s, the exact stuff also works for the USB connection problem in Xiaomi MI3 phone to access the phone files. I hope there is no such problem in connection for Windows 7 when I update to Windows 7 dumping my favorite OS: Windows XP.