I do assist customers with desktop sharing support and remote Login in certain cases, to simplify unknown areas of training.
Remote log-in allows users to connect to their own desktop while being physically away from their computer.
I use Teamviewer to accomplish this, which is a free download and does NOT permanently install on your computer. Its completely safe and used by millions of professionals.
With TeamViewer you can remotely control any PC anywhere on the Internet. No installation is required, just run the application on both sides and connect - even through tight firewalls.
Get Teamviwer here for free, and click run once it is downloaded. Its quick and easy.