Stopping remote connections

My husband started a new job and to set up an e-mail address on his home laptop, he allowed a guy in their IT department "remote access". I'm a bit worried that a stranger can now get on his computer and creep around in there any time he likes and see how he's spending his time. I know I can do Control Panel > System Security > System > Remote settings and then untick the box - is that enough to stop him getting on again? To allow the access, my husband went to a website, clicked on a box to download a small piece of software and then read out a series of numbers (3 sets of 3 divided by fullstops) and then read out 4 numbers as a password. I believe the IT guy used something called teamviewer.com to do it. He says it was a one time access only and the numbers change every time but I'm such a cynic I'm not sure whether I believe that-he might just be saying that and then sell the numbers on some hacker site and then anyone can get access. There is now a button on my husband's desktop that says the company name and then "VPN connection" which he needs to connect to every time he wants to use this new e-mail account. How do I secure his computer from outsiders please, but still allow him to use the new company e-mail. Will just unticking the box referred to above do it? (BTW Do I sound paranoid?)

go to Control Panel -> programs -> uninstall and app. is TeamViewer listed?

Teamviewer is a pretty common program and is used by a few techs on this site.

I've checked and TeamViewer isn't installed so I'm reassured by your answers. I guess he's safe but I've unticked the remote access thing as a double safeguard. Thanks to all who replied.