I bought LR 6 PC/Mac Disc, and I successfully register my LR 6 at https://accounts.adobe.com/products using the serial number in the box. But I can find nowhere to download LR 6 (There is only download links for LR CC). I just download Adobe application manager and installed LR CC. But I cannot use my serial number to activate my LR 6 on mac with error: We are unable to validate this serial number for Adobe Lightroom. Please contact Customer Support.
But things are different on Windows. I Adobe application manager and LR CC. After I activated LR with the serial number, title in LR was switched from "Adobe Lightroom CC 2015" to "Adobe Lightroom 6" and the activate pop-up window never appear again.
I am so confused why it worked differently on Window and Mac.
First uninstall the existing version for Lightroom you have installed on your system.
Restart the System, follow the below link to download Lightroom 6 and activate the product using the serial number.
Download the setup file according to the Operating System. (Windows/ Mac)
Let us know if it helps.
I downloaded LR 6 for mac and choose "install" (instead of try), it fail to verify the serial number.
I finally got it. It is due to some network problem.