Keeps running 'checking for updates' for hours

Those links do not work mate,

When manually installing updates you need to switch your update settings to Never check for updates and restart the machine first.

http://www.sevenforums.com/tutorials/2797-windows-update-settings-change.html

Make sure KB3020369 is installed if not manually install it this is the main article page with all versions,

https://support.microsoft.com/en-us/kb/3020369

These other links do prompt you to download as soon as you click on them just to give you a heads up :)

Win-7 32 bit

https://download.microsoft.com/download/C/0/8/C0823F43-BFE9-4147-9B0A-35769CBBE6B0/Windows6.1-KB3020369-x86.msu

Win-7 64 bit

https://download.microsoft.com/download/5/D/0/5D0821EB-A92D-4CA2-9020-EC41D56B074F/Windows6.1-KB3020369-x64.msu

Then manually install KB3172605 main article page with all versions,

https://support.microsoft.com/en-us/kb/3172605

KB3172605

Win-7 32 bit

https://download.microsoft.com/download/C/D/5/CD5DE7B2-E857-4BD4-AA9C-6B30C3E1735A/Windows6.1-KB3172605-x86.msu

Win-7 64 bit

https://download.microsoft.com/download/5/6/0/560504D4-F91A-4DEB-867F-C713F7821374/Windows6.1-KB3172605-x64.msu

After switch your windows update settings back to what you had prior and manually check for updates and the rest should show up shortly.

If you need visual aids refer to this as reply 1 suggests,

http://answers.microsoft.com/en-us/windows/forum/windows_7-update/windows-7-update-problems-read-this-first/28147a5f-b0b0-480b-bed9-834a2da7a375

A lot of problems arise from setting Windows Update to automatically update. Select Start, All Programs, Windows Update, Change Settings. Under Important Updates is a box showing the current setting. Click on the Arrow down to the right and change the selection to “Never check for updates”. Click on OK and restart your computer.

For a Windows 7 32 bit computer download and install:

https://www.microsoft.com/en-us/download/confirmation.aspx?id=53335 (replaced link as late edit)

For a Windows 7 64 bit computer download and install:

https://www.microsoft.com/en-us/download/confirmation.aspx?id=53332 (replaced link as late edit)

Select Start, All Programs, Windows Update, Change Settings. Under Important Updates is a box showing the current setting. Click on the Arrow down to the right and change the selection to “Check for Updates but let me choose whether to download and install them”. Restart your computer.

Current as of 1 August 2016

July 2016 update rollup for Windows 7 SP1 and Windows Server 2008 R2 SP1

https://support.microsoft.com/en-us/kb/3172605