The one I have is labeled as XPS L321X with model No: 321X-4990.

www.dell.com/.../50HWRS1

"INTEL CORE I5-2467M

4096MB (1X4096) 1333MHZ DDR3 SI

128GB SOLID STATE HARD DRIV..."

It should be GEN1. I didn't upgrade BIOS, just downloaded ISO with Sputnik OS

hwe.ubuntu.com/.../sputnik-precise-amd64.iso

put it on pendrive and rebooted my XPS with it in USB port.

I have had this problem for ages and it was driving my mad. It took me a while to get to this site.  This solution totally fixed the problem.  Thanks.

I am having the same issue but with a twist. This happens even when the computer is plugged in to a usb keyboard and mouse. No touching of the laptop at all. My boss is fed up and wants this fixed. I checked the reg key fix for foregroundlocktimeout but it was already set to 30d40. any other ideas?

We tried everything but the "stealing focus" problem is still there.

It's a new end 2012 XPS 13 model with Windows 8 Pro.

If i shut the webcam with my finger it looks like the focus is getting stolen.

I'm not sure if it's really some kind of focus stealing but it looks like it. An active browser window will get inactive.

For me it definitely is related to the Adaptive Light Sensor. I tried everything.

- Lataest Trackpad drivers --> didn't solve it

- Register Edit with 30d40 --> didn't solve it

- Windows Metro search for just start type Ambient and shut everything what was found --> didn't solve it

- services.msc and shut down Sensor Monitoring Service --> didn't solve it

- Advanced Energy settings Monitor/Adaptive Light Sensor --> didn't solve it

I'am really out of options. It looks like we can't shut the sensor down by Bios.

Any suggestions?

With tape i shut the 3 eyes, webcam and two pin holes at both sides of the webcam and the stealing focus problem is gone.

Big question how can we shutdown this Light Sensor?

Good suggestion but It looks like there's no Face Recognition Software. We have also a XPS 14 and that had indeed this awfull functioning Face Recognition Software so i know what you're talking about but i can't find anything of it on the XPS 13.

This 'stealing focus' bug makes the 2013 version of this ultrabook virtually unusable. Doesn't look like Dell are interested in fixing the problem and I'm just outside of my 7 day return window.

I had the same problem with the 2012 version! 

Seems to come and go - something about the ambient light sensor seems to significantly reduce the rate i saw  the bug. Still my favorite Ultra Laptop though.

Would be nice if Dell actually cared and told us how to fix it.

Turn off the ambient light sensor and problem goes away.  I was frustrated for a week and it has never come back

No if you search "light sensor" there is an option under control panel for Location and Other sensors.  There is a check box for Light Sensor to be enabled. Uncheck it and you should be good to go.

Thank you gglenday! Shall I switch off "adjust the brightness of the screen automatically"?

Does anyone have the WIFI device problem? my XPS has difficulty getting connected to the internet when other devices (macbook, cellphone, ipad...) work very well.

Same here!

I tried to get used to this problem but it was impossible. I had tech support helped me updating it to the newest driver but didn't help.

I called them several times but couldn't  get a chance talking with them after waiting 40min. I am out of patience.

A laptop with this kinda problem is USELESS.

I have Windows 8 and I have searched everywhere though the Control Panel and can find nothing that leads me to a Light Sensor or a way to uncheck it.  In Windows 8 is there some other way it is accessed?  A search turns up nothing.

Mary