Win10 th2 can't update how to do

Win10's first major update TH2 fall update has now started to push, many users have not received the update, and many users have encountered problems during installation, you can refer to the following to solve. The first thing to note is that the Insider users who have upgraded to 10586, you are now using the official version of TH2, no need to update.
Check if there is a postponement upgrade.
About receiving push notifications, on the one hand, it may be because your system has just been upgraded from older versions such as Win7 and Win8.1, and is still in a month's time. During the experience period, in order to ensure that you can return to the previous version when you repent, Microsoft does not push TH2 updates for the time being;

Another reason may be that you have selected "delay upgrade" in the system. ;, as shown below, if you are sure to check this option, please cancel and try again.
There may be insufficient space or SD card to cause
About installation errors. Please try to make enough space for the system partition. If you have upgraded the system before, you can clean it up. You can use the cleaning software to complete it. Deep cleanup can also be performed.

Another situation may be caused by Microsoft's already discovered SD card causing installation failures, especially for tablet devices. Please remove the SD card from the device.
Download the image upgrade yourself
If you can't find the reason, the best way is to download the image to upgrade. Even with Windows Update, the system needs to download a complete system image, except that ESD is smaller than ISO.
The only thing you need to pay attention to when downloading the image upgrade yourself is the version correspondence. Make sure that the downloaded image is consistent with the version of the system you are using. And note that the Home and Family Chinese versions are two different versions.