I'm here to announce a good news to all MIUIers. Your issues about Mi PC Suite has got a solution now. Xiaomi has released an update to the Mi PC Suite (Version 3.2.1.3041). Yes, the issues about Mi PC Suite not connecting to devices is solved in the latest update of the Mi PC Suite (Version 3.2.1.3111). With this new update, the Mi PC Suite is able to connect to the devices. For those, who are in Version 3.2.1.3041, you will get an update notification in the bottom of the Mi PC Suite, near the Version number soon. If you want, you can download the file from here. The update notification will be looking like this.

Official Mi PC Suite
You will see an upward arrow in blue color, near the version number, if you get an update. Clicking on this will ask you to restart your Mi PC Suite to the new version. After restarting the Mi PC Suite, your device will be detected in the Mi PC Suite and it will look like this.
Official Mi PC Suite
You can see the new updated version number on the bottom left of the Mi PC Suite. Note that the version number has changed now.

Download the New Version of Mi PC Suite from the link below.
MiSetup3.2.1.3111

Note: Android 6.0 Marshmallow devices is not supported in this version of Mi PC Suite.

Source: Xiaomi Device