Unknown computers have connected to my personal wireless network

[Guest]

My new security program, Trend Micro PC-cillin, keeps interrupting whatever I
am doing with a window which lists in 2 columns, IP addresses (& numbers) and
MAC Address. I Can NOT get rid of it. It has a choice of giving each a
"Trust" or "Do Not
Trust". Even though I click on "Properties", it tells me nothing of who
these computers are. So, I can not choose either. What do I do? I do not
understand any of these numbers. Even though I click "Close", immediately,
the box pops up again. I sent a help email to Trend Micro but no response.
Do any of you know how to deal with this?
Donna

 

[DP]

Do you have any kind of security for your network? Like requiring a
cryptographic key to be able to connect to it?
If not, you should.

 

[Guest]

DP, Thank you for responding. Trend Micro finally answered me after 2
weeks.
I have no idea what network security my server has. Could you tell me what
a cryptographic key is; how I get one, & how I would connect to it. I have
little knowledge of the technical side of computers. Donna