Windows 10 upgrade not received

I am running Windows 8.1 x64 with all the latest updates from Microsoft. But still when I click on the GWX icon on the system tray it says "We are still evaluating your PC for the update".

People have already received the Windows 10 upgrade. Can anyone tell me why this is taking so long for me? Any suggestions would be helpful.

Patience…

The servers are trying to roll out to several hundred million users. Your turn will come.

If you really can't wait, you can force the upgrade by getting the Media Creation Tool & running the install manually from a USB stick.

From comments…

Don't try to install by booting from the USB stick, as this would invalidate your free upgrade & you'd need a true Windows 10 key to install.
Without that key, it will reject the install & tell you to run it from inside your current working OS instead - by booting as normal, then running the setup.exe on the stick.
That way, when you get to the install key window, you can skip it & it will authenticate based on your existing install.

The USB stick isn't compulsory - if you have only a single machine to update, you can just run the tool straight from that computer. The USB stick saves multiple machines needing multiple 4GB downloads.
The options are something like [not verbatim]
'Upgrade this machine' & 'Upgrade another machine'
'This' will download & upgrade just that machine, 'another' will allow you to construct a bootable installer on USB, which can be run at boot, or from a running system.

In addition to what has been said about the media creation tool there are sometimes valid reasons why you have not received the update yet. There are still some known compatibility issues and drivers that are pending fixes and updates, and if the update utility detects that you fit one of those scenarios then it will not offer you the update until they are fixed.

One example can be found here. Once things like this no longer need a workaround then that category of computer will be upgraded.

You can use the following command in the cmd.exe to get the windows 10 download started in the windows-update application:

wuauclt.exe /updatenow