Last week, Microsoft accidentally (?) revealed the download links του Windows 8.1 Update 1. So many people installed the upcoming Windows update, believing it to be RTM.
Microsoft quickly removed the links to prevent others from installing the update, but that's not the case as the archives they are now all over the dianetwork.
While all this happened, the Chinese website PCBeta reports that build 17031 is not the RTM that everyone thought, meaning that those who installed it will probably need to reinstall their OS system as soon as the final version of the update is released.
Although no one can say for sure whether this publication is accurate or not, the build currently on the web seems to be very close to the stable build, as most of the features that are said to be included in Windows 8.1 Update 1 was already there.
On the other hand, this whole story can teach a lot of people not to hurry and not to install in their system that they show on the internet, especially when it is not officially announced.