Before you start Windows Update (WU), if your computer has not been up and running for a few days or more, start it and let it run without using it for some hours. Turn off the sleep functions if they are set. If yours is a laptop, make sure it is powered with the power cord. Start Task Manager (right-click on the task bar) and look at the CPU % in use at the bottom of that window. If it is more than 10%, you have to wait until what ever the computer is doing finishes before starting Windows Update.
Functions like Antivirus update and scans, scheduled defragmentation, updates to Java, Flash Player, Adobe Reader and others must be completed BEFORE you start Windows Update.
I just did this on a laptop that had not been used for about 70 days. It took the best part of a day to finally settle down and be ready.
Windows Update is dramatically slower than it was in the Spring of 2015, before Windows 10 began downloading. There may be nothing wrong with your computer! The problem is a hopelessly inadequate Windows Update service. Likely it is overwhelmed sending millions of unrequested 5 gigabyte Win10 files to Win7 computers, using the same equipment and network that normally services you and I.
From Microsoft’s perspective, the updates you want are an extremely low priority. They do not want you updating Windows 7. They want you replacing it with Windows 10.
There is no reason to do this upgrade unless you are a real adventurer. Windows 7 will be supported through January 2020.
I have seen cases where the green bar in Windows Update continued overnight and finally found the updates, then spent many more hours downloading those updates.
Turn off sleep and hibernate functions. Leave WU running at least overnight, maybe longer
Check to make certain the 4 needed services are starting properly. If any one of the services, were not already started, type services in the text box above the start globe and find each of those services in the list (list below). If they are not set to automatic, double-click the service and set. You can do this while Windows Update is running.
Background Intelligent Transfer Services, Cryptographic services, Windows Installer, Windows Update. They should be shown as Automatic or Automatic (delayed). If they are not, double-click on each as necessary, and change setting to Automatic.
Set Windows Update settings to NEVER before you start. This is the setting you will keep. The never setting will prevent that phenomena where WU is running and then you check and see an yellow exclamation point on the shut down button. That situation results in a kind of tug of war between competing WU rivals.
Check Task manager BEFORE you start WU. If your system is very busy, it may produce that 80070490 error and that “try again” button. Wait and watch that % at the bottom of the task manager window for a while untill it settles down to below 10%. Then try again.
Next, we need to prepare your system to properly handle Windows Updates. It will take a long time (like a day or more), but in almost all cases this gets Windows Update back on track.
- Download and run the correct version for your system of the System Update Readiness tool KB947821. https://support.microsoft.com/en-ca/kb/947821 32 bit systems need X86. 64 bit systems need X64. This is likely to take a while (could be many hours) because it doing all kinds of resets.
- Download KB3102810 directly from the Microsoft web site and install it. https://support.microsoft.com/en-us/kb/3102810 32 bit systems need X86. 64 bit systems need X64.
- Download KB3168965 Windows 7 64 bit version: https://www.microsoft.com/en-us/download/details.aspx?id=532096
Now re-start Windows Update. Do NOT restart Windows. Be very, very patient, it will likely take a long time. Recently, the whole process has required 24 hours or more elapsed time in my work on my client computers.
Now, your challenge is to be PATIENT. This may take many hours.