Take a look here, it applies to CS6 as well
Failing that you could try manually downloading the update from here
Looks like I got it fixed but not in the way mentioned above. As I have a MAC then this explanation did not apply to me. But here is what I did:
When I initially tried to update CS6, I opened Photoshop and click help/updates. This gave me an error that server is not responding. So I downloaded Creative Cloud App manager. And after downloading and installing, I went back to CS6 and clicked again help/updates, and somehow now it works. It seems that you can't do any direct updates from software without downloading CC App manager. Although CC App manager will not show me any of my installed apps and I can't update them through there as I am not using Creative Cloud.
Hope this explanation will help others as well.
Maybe you should have mentioned in your original post that you had a MAC.
At least you got it sorted
My notebook is Windows 10 Pro.
I still got the same error, update server is not responding, after I downloaded and applied "
Downloaded Creative Cloud (including App manager) then clicked "update..." from CS6 that worked great as MartinHallik.
Thank you for both of you.