Many new PC’s, notably Macs no longer come with a disk drive. You could make a copy of the download to a disk or thumb drive. You can buy from the following link. After clicking "Buy" change from Full to Upgrade; then select your existing LR product from the drop-down menu and the correct pricing will be displayed. Then simply choose “Add to Cart”
Or you can take a 30 day free trial via the Creative Cloud to test what’s new (some new features are only available to CC subscribers) and after the trial it’s possible to convert the CC version to the LR6 stand-alone version, upon purchase of a serial number and without any further installation. In either case make sure your computer meets the minimum system requirements.
Minimum system requirements
The download will always be available if you should ever need it again.
The latest download is available at the links here: Lightroom CC 2015.1.1 is now available
Save the links, rather than save the download.
Yeah, I get both answers - so thanks guys. I guess I'm a little old fashioned. I just find things so much more straightforward using a disc.
It seems to me that Adobe is only interested in promoting CC. I realise that this is the future and no doubt the majority of their customers are large organisations and commercial studios. I'm sure CC is financialy viable for these customers, but it isn't so viable for us ordinary amateur photographers, unless we have large disposable incomes.