dnvm updgrade access to temp directory denied

Hi everybody,

I have a problem installing asp net 5 in visual studio community 2015 Update 1 in windows 10.

I followed this guide https://docs.asp.net/en/latest/getting-started/installing-on-windows.html#install-asp-net-5-with-visual-studio and installed visual studio community 2015 update 1 and then asp.net 5 from get.asp.net, but when I run dnvm upgrade from the command prompt (or from powershell) I have this error message:

I tried also to reinstall both visual studio and asp.net 5 but I still have this problem. Is there any solution to fix this issue?

Many thanks.

Alberto