Here's what I have tried so far:

Down load to PC. Run it. it shows a picture to plug some thing in. Plug drone into PC. Turn drone on. Nothing happens. When I go to leave it ask if I want to leave. Down loaded it 3 times.

Ipad II. Down load. Start progam. It dispalys"searching for device". Drone plugged in and wireless on. Nothing happens.

Iphone SE. Same results when I tried the PC. OK, what am I doing wrong? It has to be some thing simple.

when you plug drone into PC or any device, do you switch it on ? It needs to be powered up.

It was Aardvark. Just tried again with the Iphone, it was the only one I was uncertain about.

We tested the cord. It looks like the DJI Iphone USB adapter is bad. I am going to buy another from BestBuy to see if that is the issue. That may be the problem with the Apple devices.

AnchorageAk Posted at 2016-11-8 20:58
We tested the cord. It looks like the DJI Iphone USB adapter is bad. I am going to buy another from  ...

And for the pc it loads a USB driver as part of the install. If that's been skipped it won't work.

You have a P4 correct?
What is the reason for wanting to use the Assistant2, if it's for updating firmware then this can also be done from your phone/tablet.

DJI-Ken. It looked like a neat way to find updates, and do updates. I was able to update the two P4's I have with the app. So what really is the purpose for the assist?

Aardvark I give up. I will just use the app. I have reached my limit. Some thing so simple should work. It isn't hard to follow. We tried the lap top to. Same issue, can't find device. Apparently, from what I am reading, I really don't have a need for it. The dog you see is a Gordon Setter. They started life in England. From the Duke of Gordon.

AnchorageAk Posted at 2016-11-10 02:06
DJI-Ken. It looked like a neat way to find updates, and do updates. I was able to update the two P4' ...

You will need Assistant 2 to calibrate the 'sensors' (Obstacle Avoidance and Positioning cameras), or refresh the firmware, or factory reset. It is possible that there may be some conflict with anti-virus software etc (you could try disabling during installation). When installing you could try running in 'Administration' mode. And there is definitely a popup about the USB driver, although I can't remember if it needs any input. I'll maybe try here.

A lovely dog

That would be the Gordon Clan

Just to clarify, what OS are you running? Please try Aardvark's advice and let us know if the issue persists. In addition, you may want to completely uninstall, then reinstall the Assistant 2 software to ensure that the driver for the P4 was installed. Ensure that the aircraft is connected to the computer when doing so.

Windows 10.

We just tried administer, with anti virus turn off. No change. Here is a picture of the screen. Also, tried the front, and back usb ports. Also, different cables, and a different drone.[img]https://forum22.djicdn.com/data/attachment/forum/%5BURL=http://s141.photobucket.com/user/AnchorageAlaska/media/15c6d026-4882-44c8-b6b2-7b187e34c089_zpsyifkigrm.jpg.html%5D[/URL][/img]

AnchorageAk Posted at 2016-11-10 21:53
Windows 10.

We just tried administer, with anti virus turn off. No change. Here is a picture of the ...

OK, at that point I would normally plug P4 into USB on computer and power up P4, you may also need to login to your account.

After a few seconds you should see a P4 icon appear on screen.

AnchorageAk Posted at 2016-11-11 05:53
Windows 10.

We just tried administer, with anti virus turn off. No change. Here is a picture of the ...

When you reinstalled the software, did you happen to restart your computer? During the install, did you see the option to install the driver for the P4?

The picture says it all, will sort of. We plugged it in. Tried the front usb, and my wife saw a video about using the usb's off the mother board in the back, still did not find it. It was powered up after the program was up. Tried powering it up before the program came up. We are using two different computers. We did not restart the computers after the install. I guess I can try that. But, we  aren't getting that driver, because of some thing. On the bright side, it is raining and snowing out. Good day to learn more stuff about the P4. Another month or two I will be able to tell the front from the back. I am going to go to some one else's house, and try it there. As I keep saying, it has to be some thing simple. We found on the net where a few others had this problem. One guy send his back to DJI. The odds of both P4's being bad is very hard to believe. We have also changed all cables.

Well this has been an adventure. I restarted the computer, and guess what? It worked. Did the same thing yesterday. It didn't work. This evening got the message "windows firewall blocked some features of this app".
It isn't mine to reason why, but I do have to wonder. Thanks every one for your help. I'll not going to touch a computer for a few days.