TX2 :Error:CUDA cnnnot be installed on device

when I want to install CUDA on my tx2 board,I face this problem.
I have alreay flash my borad,but I didnot install CUDA.So I connect my borad and my host pc with wlan wire.And I am sure that both my board and my host pc are connected to Interet.
I input nvidia nvidia on my host pc as need.
But the problem appears.
I get a screenshot as the following:

This is just a wild guess…I see:

Connection to closed.

…then errors show up. You mentioned wlan…WiFi itself is not supported, and if this is WiFi, try as wired.

Second wild guess…make sure your host doing the flash has the “ssh-askpass” package…if not, then JetPack doesn’t have a way to present an ssh pop-up for entering a password.

I am sure I install with wired.
As for the second guess,could you give me some instruction as detail as possible.

On Ubuntu (host side) see if this installs:

sudo apt-get install ssh-askpass

…if it shows that it wasn’t already installed, then there is a good chance that attempting to install packages again will work after it asks for a password.

I have already solve this issue.I delete all the download files and re-execute JetPack-L4T-3.1-linux-x64.run and then follow the rest workflow.
After that I can successfully install the tookits.

ya, a clean install does the trick - thanks for the update.