It's not the router, it's the mouse and/or keyboard.

yep I would say disable his wireless mouse and keyboard and see if it stops, someones wireless is messing with the other try setting different frequency for them.

We are far from each other, I think way too far for either mouse to work. Three story house, son in basement, me on the third floor. I have a 'wired' keyboard and he uses his laptop keyboard but does use a wireless mouse. I'll turn off his mouse, but it only happens when we are both on-line at the same time. No trouble when I'm working off-line.

Jane

I missed the distance between the two machines. Hmmm. That's kind of odd. When you say "online" you mean when you are using a web browser? Technically, if you have a wireless connection you are "online" whenever the machine is powered up.

Do you use a wireless mouse?

Yes we both use wireless mice. We are too far away for either to interfere. I think somehow both machines are sharing a signal to the router or the router sees both machines as one machine.

You are right, even when I'm not on the internet it is affecting my work and making the cursor move and highlights text. It only happens when he is using his computer. I don't know whether to deal with Linksys or call in a tech.

Thanks,
Jane

I really have to believe it is the mice, especially since it only happens when your son is using his cordless mouse and what you are seeing on your screen mimics what a user might be doing on another screen. It's not just random motion caused by inference but deliberate motions made by a person. One way to rule it out is to have your son not use a cordless mouse. Or buy a cheap, corded mouse (which isn't a bad thing to have in your closet for emergencies) for your computer. If the problem goes away, then it's the mouse. Try a different brand or call their tech support.

I'd be looking at ip and mac addresses for duplication or clone,,, and knowing you use remote desktop .. those configurations too.

Could it be the son has installed one type of the remote desktop ,,, maybe its running full time on same ports?

Thanks, Mikie. I have a tech coming over tomorrow. This stuff is sooo way beyond me. I don't understand any of this wireless business and am so frustrated trying to figure it out myself. I need someone to look and see what is happening. Knowing me, I probably checked, or unchecked something and its messing up the signals.

I'll post when I (hopefully) get it fixed.

Thanks again,
Jane

Update. Mike and Mikie win the prize! First off I gave my son a wired mouse and the weird moving cursor stopped. I still find it hard to believe as the distance is really far, but it must have been. He was using a Longitech mouse and I, a Microsoft. I had a tech come to the house and he said they were too far away to cross signals, but it hasn't happened since my son started using the wired mouse. His mouse was a small, laptop type with the little flash plugged into the computer.

What makes it even more weird, if he tries to use his mouse more than 5ft from his laptop, it doesn't work! Yet we must be at least 100 ft away from each other and on different floors.

I'm still not completely convinced, but so far I haven't had the problem again. The tech did find a bigger problem with my desktop and I will start a different post.

Thanks, guys...you are genius!

Jane