Update to Windows 8.1 not in store?

[Kanbabrif]

That might be the case if you are using an illegal key.........
Is your Windows 8 install legitimate?

Volume licensed installations of Windows 8 are not eligible for the store upgrade. If your environment is licensed through a volume licensing agreement, you will need to access the Windows 8.1 media through the Volume Licensing Service Center.

Brandon
Windows Outreach Team- IT Pro
The Springboard Series on TechNet

A friend of mind brought his Windows 8 disc which he bought at Staples and installed on my computer.

 

[Yevrag35]

A friend of mind brought his Windows 8 disc which he bought at Staples and installed on my computer.

If he bought it, didn't he already use the retail license then? Or did he buy it specifically for you? I don't know if he bought a multiple key version, but most of the time, the license is only good for 1 computer.

 

[carnageX]

A friend of mind brought his Windows 8 disc which he bought at Staples and installed on my computer.

Did you use his key or your own key?

 

[glomicilina]

Hi! maybe you need a first patch.
look for "Windows8-RT-KB2871389-x64.msu"
install it and then go to the store and check