Microsoft announced back in November that they are going to reduce the free storage from 15 GB to 5 GB and will stop offering additional 15 GB camera roll bonus. This will be effective from the beginning of next year. However, they are offering existing customers to keep their free storage by opting in before 31 January 2016. If you have got any other bonus storage via different channel, i.e., Samsung offered 100 GB free Microsoft OneDrive cloud storage for two years with Galaxy S6 and S6 Edge. You can’t keep that free storage forever, it will stop once the subscription ends.
This free offer requires you to opt-in for Microsoft’s emails which you can opt-out later.
To keep your free Microsoft OneDrive 15 GB + 15 GB camera roll, log-in to your OneDrive account, click on this link. Click on “Keep your free storage”, allow or accept the option and the next page should display that it is done. Painless and easy process. I’ve just done it for my account.
If you don’t have an OneDrive account yet and want to get total 30 GB of free cloud storage, register for a free account using any email address. It will give you 15 GB free. Download the OneDrive app in your phone tablet and turn on camera upload to get additional 15 GB free. This is what new customers will not get from next year.[Source]