Win 7 Pro x64 Updates not working at all, errors 800736B3 and 80246007

Sorry for the delay!
The problem with this error is that it's relatively rare, and tends from what I can make out to be caused by severe registry corruption - although it's possibly the result of (another) failed updated from MS.

In your case, there is come corruption in the SFC scan...

Code:

 Line 5762: 2015-03-18 19:52:34, Info                  CSI    000003d5 [SR] Repairing 3 components
 Line 5763: 2015-03-18 19:52:34, Info                  CSI    000003d6 [SR] Beginning Verify and Repair transaction
 Line 5766: 2015-03-18 19:52:34, Info                  CSI    000003d8 [SR] Cannot repair member file [l:24{12}]"cryptdlg.dll" of Microsoft-Windows-cryptdlg-dll, Version = 6.1.7601.18150, pA = PROCESSOR_ARCHITECTURE_AMD64 (9), Culture neutral, VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch
 Line 5769: 2015-03-18 19:52:34, Info                  CSI    000003da [SR] Cannot repair member file [l:26{13}]"tzres.dll.mui" of Microsoft-Windows-International-TimeZones.Resources, Version = 6.1.7601.18588, pA = PROCESSOR_ARCHITECTURE_AMD64 (9), Culture = [l:10{5}]"sl-SI", VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch
 Line 5772: 2015-03-18 19:52:34, Info                  CSI    000003dc [SR] Cannot repair member file [l:26{13}]"tzres.dll.mui" of Microsoft-Windows-International-TimeZones.Resources, Version = 6.1.7601.18588, pA = PROCESSOR_ARCHITECTURE_INTEL (0), Culture = [l:10{5}]"sl-SI", VersionScope = 1 nonSxS, PublicKeyToken = {l:8 b:31bf3856ad364e35}, Type neutral, TypeName neutral, PublicKey neutral in the store, hash mismatch

I'll post a fix protocol for these when I can.

I've uploaded a file - eusaa.zip - to my OneDrive at Noel's OneDrive
Please download and save it.

Right-click on the saved file and select Extract all...
Change the target to C:\ and click on Extract
Close all windows (it would be a good idea to print these instructions!)

Now reboot to the Repair Environment - as soon as the machine restarts, start tapping F8 - this should bring up the Advanced Boot Menu, at the top of which should be the option 'Repair my Computer'
Pick that
You'll have to log in with your username and password.

Pick the option to use a Command Prompt
At the prompt type
DIR C:\eusaa
hit the enter key - if you get a 'Not Found' error try
DIR D:\eusaa
or
DIR E:\eusaa



The drive letter in use when you find the folder will need to be substituted (for<drive>) into the following command...



XCOPY <drive>:\eusaa <drive>:\windows\winsxs /y /i /s /v /h



(e.g. XCOPY P:\wfire P:\windows\winsxs /y /i /s /v /h )



run the command (it should take almost no time) and when the prompt returns, type
EXIT
and hit the Enter key to exit Command Prompt - reboot to Normal Mode Windows.

Now run SFC /SCANNOW in an Elevated Command Prompt
then reboot and upload the new CBS.log file to your reply

the SFC scan is clear

So - does Windows Update now work? - what is the new error message (if any) after doing a Check for Updates?