Solution - Windows Update Can't check for Updates

Problem - Windows Can't check for Updates. These steps resolved the problem on my computer, but expect to take an hour or more to run -- plus the time it takes to catch-up on the Windows updates, once fixed.

Symptoms:
Windows update System Tray icon reports "Windows can't check for updates"
The Windows Update Status indicator runs, but shows no activity or
The Windows Update Control Panel Page shows a Red-shield icon and warns you should run an update regularly, but it does not actually run the update.

Reason:
Windows Update may have become corrupted.  Microsoft has a utility that fixes this problem.  This problem can especially happen if an older computer is brought online after a long period without updates.


You can run this utility even if you are not sure the symptoms match your problem.  There is no harm in running this utility, other than taking time.


Steps:

1.  Confirm the PC's Date and Time are correct.  (Click the time in the lower-right System Tray).

2.  Launch Windows Explorer (i.e. File Explorer, not IE).  In the tree-side, locate "My Computer" (or "Computer").  Other-mouse-click "My Computer" and choose "Properties" from the context menu. 

Note which Operating System is installed, which Service Pack, and whether it is 32 or 64-bit.

For example:
Windows 8 64-bit  SP1
Windows 7 64-bit
Windows Vista 32-bit SP2, etc.


3.   Decision: Windows 8.x / Server 2012:

If Windows 8.x, Windows Server 2012

a.  Open the Start Menu, locate the Command Prompt icon, but do not click to open.  Optionally, swipe from the right side of the screen and search for "Command Prompt", but do not launch.

b.  Other-mouse-click the Command Prompt icon, choose "Run as Administrator".  This runs DOS as an "elevated command."

c.  Type these two commands, pressing Enter after each.  The commands may take several minutes to run:

DISM.exe /Online /Cleanup-image /Scanhealth
DISM.exe /Online /Cleanup-image /Restorehealth

The install takes about 60 minutes and may have long hesitations on the status bar -- allow it to complete; note the hard drive light will be busy even if the status bar does not move. 

d.  Close the DOS Command Prompt window.  Open the Control Panel, run Windows Update manually; the problem should be resolved. 


If Windows 7.x, Vista, or Server 2008

a.  Using Internet Explorer (it must be IE), go to this site:

http://support.microsoft.com/kb/947821

b.  Scroll to the Windows 7 section.

c.  Download and run the correct version (noting which version of Windows, 32 or 64-bit, etc.).  The install can take up to an hour and may have long hesitations on the status bar -- allow it to complete; note the hard drive light will be busy even if the status bar does not move.  Microsoft notes this tool, the "Windows Update Standalone Installer" is updated regularly and you should always use the most current version.

d.  Open the Control Panel and run Windows Update again.  The problem should be resolved.


4.  If you are still having problems, this low-risk solution has been reported to help, although I have not needed this in my experience.

a.  Start an elevated Command Prompt, as described above.

b.  Type this command and press Enter.  Then attempt the Update again.

netsh winhttp reset proxy


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