Windows update Error 80070490

Please follow the Windows Update Posting Instructions and post the requested data

OUCH!
The CheckSUR log shows the following summary...

Code:

Summary:
Seconds executed: 556
 Found 2498 errors
  CSI Missing Deployment Key Total count: 294
  CSI Payload File Missing Total count: 4
  CBS MUM Corrupt Total count: 2
  CBS Watchlist Package Missing Total count: 1562
  CBS Watchlist Component Missing Total count: 636

I could possibly cope with 20 or so Deployment Keys, and similar numbers of Watchlist - but this is an extreme case of corruption.

I can really only suggest a repair install
See the instructions here... Repair Install

You can't - you will have to do a repair install, due to the huge number of problems in your current install.