If you are using teamviewer 10 host's on the remote pc than they need to instal a free version of any kind of teamviewer on their pc and then give the technician the id and password so he can connect to that pc. And if you want to connect with them again after the technician is done with the job they need to close or delete that teamviewer and open the teamviewer host again so you can remotly connect!
I hope this helps.
Thank you for using teamviewer.
With kind regards, Met vriendelijke groet, Iain Wels, ICT-Support If you found this helpfull please verify it as an solution, so it could help other people