How do I download 360 on a new computer from an existing account?
First and very important -- does the new PC have any security software on it pre-insstalled eg as trial software?
If so what is it -- Norton or another make -- details please since this can cause a subsequent installation to not run correctly.
After giving us those details we can provide instructions on how to ensure your PC is clean.
Meanwhile make sure you have a copy of the KEY used to activate the Norton 360 which you can get from the MyNortonAccount and make absolutely sure that you know exactly which sub-version of Norton 360 since as you will see below there are 4 and the KEYs are not interchangable.
When you have all that together and have cleaned up the new PC -- the only time that would not be needed would be if it had exactly the same product and subversion as you have the KEY for -- you can download a single file to install from:
New N360 V5: Click on the link that matches your version:
Norton 360 v5 Standard: http://www.norton.com/n360s_5/ << version with 2GB of online storage
Norton 360 v5 Premier: http://www.norton_com/n360p_5/ << version with 25GB of online storage
Norton 360 v5 Standard Netbook Edition: http://www.norton.com/n360sne_5/ Netbook Edition << version with 2GB of online storage
Norton 360 v5 Premier Netbook Edition: http://www.norton_com/n360pne_5/ Premium Netbook Edition << version with 25GB of online storage
Make sure you get the right version since the keys are not interchangeable. SAVE the file where you can find it -- do not run it from the download site when Windows asks what you want to do.
You can download that file on any computer and transfer it to a thumbdrive to install on another. If the new PC has WIndows 7 (or VISTA) on it you should start the installation by Right Mouse Clicking on the downloaded file and selecting Run as Administrator since I find this tends to give better results.
When it asks you to activate it you can click on Renew and enter the key there.
So please don't do anything about actually installing until you have told us about the existing security and got clear instructions on how to deal with it.