Microsoft has finally started the registration of its Windows 8 upgrade program, which is available on the company’s official site for Rs.699 or $15. Announcing the upgrade on its Twitter account, Microsoft has included 90-days of no-charge support for those who purchase Windows 8. This trial period of 90 days begin when users install and activate Windows 8 on their PC.

For ₹699, users who bought a Windows-based PC after June 2 are entitled to get an upgrade to Windows 8 Pro. This offer comes for customers in about 140 countries, who have time until January 31 to redeem the offer that can be done with the company’s official webpage.

This promotional offer by Microsoft is limited to one upgrade per qualified PC purchased, and is good for up to five different PC’s upgrade per customer.

Those who miss this offer will have to pay full amount of $40 to get Windows 8 on their PCs.

This nominal price offer can be a move by Microsoft to attract Windows users to a completely different OS.

The process, however, is simple. Users just need to login to the site, choose country, fill out a basic form, with some personal information on contact number, email, Windows 7 PC, along with the place where it is bought from.

Registration of Windows 8 upgrade for users in India can be done at

Similarly, users can choose their own country from the listed 140.