Windows 7 update KB4523206 fails with the error code 80242016. According to this post some others have the same problem. However, no solution has been provided at the moment. How can I install the update?
With the help from an old page at Answers.Microsoft (2009)
Windows Update error code 0x80242016 = WU_E_UH_POSTREBOOTUNEXPECTEDSTATE The state of the update after its post-reboot operation has completed is unexpected.
(ie., Some software can be stopping the update before the machine is being rebooting, not allowing it to complete properly.)
I suggest you check for malware / virus's, etc., stop or uninstall any 3rd party firewalls.
Create a shortcut on your desktop using the system Cleanup Manager:
Right-click the Icon and choose Run As Adminstrator and choose (C:) Let it run through the process and it should give you an options box Check the boxs
[x] Service Pack and Backup Files [x] Windows Update Cleanup <-- You might not find this listed
If you have never run Cleanup before it will probably take a while to finish...
Then try running the "Deployment Image Servicing and Management".
DISM /Online /Cleanup-Image /ScanHealth
Enter your Temp folder (both in User.... and Windows\Temp and remove older files (older than a week, maybe even older than two days).
Hope this helps.