I have got an HP laptop with a genuine activated Windows 8 namely, "Windows(R), CoreSingleLanguage edition". I upgraded to Windows 8.1 and few months later it started giving me messages saying that Windows license is going to expire soon! I googled, and it turned out to be a general -temporary- issue that other users faced too. so, I just ignored it hoping that it will go away, but it didn't! So I activated Windows using Microsoft Toolkit, and it only gave me 45days "remaining grace" and once it hits 30 days the "windows license is about to expire message" comes again! So, now I have got a genuine Windows 8.1 pro key and I am trying to upgrade my SingleLanguage windows to Pro, but I cannot; since it tells me "cannot add features to this edition of windows". I uninstalled KMS and did a rearm, but the message stills comes up and I cannot upgrade. I also got a genuine windows 8.1 key (not pro) but I cannot activate winows with that too! (I guess because it is the CoreSingleLanguage editio) What shall I do? how can I upgrade to windows pro?