Stuck at "Checking for updates"

http://www.canadiantech.info/for-techies/windows-update-not-responding/

There may be nothing wrong with your computers!  The problem is a hopelessly inadequate Windows Update service.  Likely it is overwhelmed sending millions of 5 gigabyte malware Win10 files to unwilling 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.

Excellent read  http://www.infoworld.com/article/2953655/microsoft-windows/windows-10-review-hold-off-if-you-use-windows-7.html#tk.ifw-infsb

I have seen cases where the green bar continued overnight and finally found the updates, then spent many more hours downloading those updates.

If yours is a notebook PC, turn off sleep and hibernate functions.  Leave WU running at least overnight, maybe longer

Stop trying to fix your computer.  You are likely to make a mess of it for no benefit.

Trying to fix your computer may be pointless, when the problem is your supplier.  Sort of like taking a part your car’s engine because it does not start, when the problem is the gas tank is empty.

One tip:  Check to see if BITS is corrupted.  If it is, solutions get a lot tougher

Start, All Programs, Accessories, right-click on Command prompt choose Run as administrator.  In the black box type net start bits.  If BITS is corrupted, you will know by its response.

If BITS is ok, it is likely simply a matter of waiting a long time — by that mean a day or so.