I am having a similar problem. Keyboard worked great for about 2 weeks and now it is completely unresponsive, despite showing fully charged. I called Dell support and they had me reinstall the OS, load the most recent service packs and still no luck. I was promised a new keyboard 2 weeks ago and have now been told an 'engineering problem' has been identified and the keyboards are backordered. At this point I'm not sure when I will have a working keyboard.

My Mobile Keyboard also stopped working (and tablet is partially behaving like the Slim Keyboard is connected). On my 4th day of owning the tablet (yesterday) I was using it with the Mobile Keyboard like normal. It was working like normal. Then I closed the tablet to the keyboard (laptop style) to put it to sleep. Less than an hour later I opened the tablet back up. Had to hold the power button for over 1 second to wake it up (which seems normal) and had to wait 5-10 seconds for everything to be responsive before I could attempt to log on (which also seems normal). However, the keyboard wasn't working, so I couldn't actually login. The touchpad wasn't working either. I also couldn't get the on-screen keyboard to appear when I touched the password field. I then disconnected the Mobile Keyboard and was then able to login using the on-screen keyboard. I then reattached the Mobile Keyboard. The result was the same. The keyboard and touchpad don't work and the on-screen keyboard won't appear either. I also noticed that the display rotation is locked to landscape just like when the Slim Keyboard is connected (odd). The Slim Keyboard is still working fine though. I can swap the Mobile Keyboard for the Slim Keyboard and the Slim Keyboard works as normal. But reattaching the Mobile Keyboard yields the same problems. I have also rebooted the tablet with the Mobile Keyboard attached and without the Mobile Keyboard attached. No progress. The tablet clearly knows that a keyboard is attached as shown in the Device Manager and by the changes in behavior. But it is not functioning. By the way, the keyboard battery had over an 80% charge when this problem happened. Currently it still over 70% charge (which does appear correctly in Windows when the Mobile Keyboard is connected. Any suggestions?

My Mobile Keyboard also stopped working (and tablet is partially behaving like the Slim Keyboard is connected).  However, the keyboard wasn't working, so I couldn't actually login. The touchpad wasn't working either. I also couldn't get the on-screen keyboard to appear when I touched the password field. I then disconnected the Mobile Keyboard and was then able to login using the on-screen keyboard. I then reattached the Mobile Keyboard. The result was the same. The keyboard and touchpad don't work and the on-screen keyboard won't appear either. I also noticed that the display rotation is locked to landscape just like when the Slim Keyboard is connected (odd).  I have also rebooted the tablet with the Mobile Keyboard attached and without the Mobile Keyboard attached. No progress. The tablet clearly knows that a keyboard is attached as shown in the Device Manager and by the changes in behavior. But it is not functioning. By the way, the keyboard battery had over an 80% charge when this problem happened. Currently it still over 70% charge (which does appear correctly in Windows when the Mobile Keyboard is connected. Any suggestions?

Same problem as above except don't have a slim keyboard, I'm not sure if it does or does not show up in device manager as device manager does not change when I unplug it. Plus my battery percentages are different than the previous poster's.  Tried on two different Dell 7130s (I5 and I3), and same issue.  Tried fixes on i5, same issue.  I3 didn't need the registry fix bec I already had ran the .exe fix from dell drivers dl.  Restored one to factory, same issue.  Tried someone's suggestion to install touch panel update without keyboard attached, but still not fixed.  Looks like I'll be calling dell for a return.  Just wasted over an hour. 

My dell venue 11 pro detects the keyboard's battery and even removes the on-screen keyboard when I attach the mobile keyboard.

No key strokes or mouse input is detected by my tablet though. Very strange.