Teamviewer is a great piece of software with a wide range of uses, for helping others with troubleshooting issues and software problems.
For the remote session to work, you need to download the TeamViewer application that is free from www.teamviewer.com
How to download:
Steps

1 Click on "Download" button.

2 Choose to "Run".

3 Choose "Run only (one time use)" setup.
4 Select "Personal/ Non-commercial use" for personal use.
5 Click "Accept - finish" after selecting your options.

Click and run the installed TeamViewer program and you are now ready to start a desktop sharing session with a partner who has TeamViewer installed on their computer.
However, to connect to another computer, TeamViewer has to be running on both machines. In order to establish a connection, generated ID number and the password of either client are required.
Therefore, you'll need to provide your ID number and password to the other person who is assisting or troubleshooting your PC.