This information applies to all versions
First of all, please make sure that an internet connection is available.
Is an anti-virus/firewall/proxy or other security tool running which might be blocking the activation? If so, please try temporarily disabling it, and see if the activation succeeds.
We recommend activating the Nik Collection in standalone mode, rather than as a plug-in. Please double-click any Nik Collection plugin icon to launch it this way.
If you are on Windows and use version 6 or older, right-click the program icon, choose "start as administrator, " and see if that allows you to activate.
If this does not work, please contact customer support and provide a screenshot (jpeg) of the error you see when trying to activate, so that our customer support can assist you.
Please click this link to request help from the DxO Support Team.