Hi man, thanks a lot for looking into my case!
If windows repair pro can in principle fix my problem, I would definitely buy it. Even the free version saved me 3 times in the past, so I didn't have to reinstall the OS.
I tried everything you suggested, things didn't look so promising, as I might have some serious issues with the win 7 component store.
Here is what I did:
1. I manually installed KB3177467 a few days ago, thinking it would solve my problems. It installed successfully.
2. Today I tried to install KB3126587, failed with the error 80070490 again.
3. I ran SURT, it completed the process after an hour, and generated 4 files, attached in my reply: CheckSUR.log, CheckSUR.persist.log, DeepClean.log, FilterList.log
I was able to get about 400M more disk space after running SURT, I guess the size of the winsxs folder is reduced after running SURT
4. I tried to install KB3126587, failed with the error 80070490 again.
5. I ran sfc /scannow(not in safe mode), found integrity violations, and SFC says it repaired issues. Note that I had run sfc /scannow multiple times in safe mode in the past, and none of those times reported any integrity violations.
I used the command findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >"%userprofile%\Desktop\sfcdetails.txt" to get only the SFC-related entries in my CBS.log and attached it here.
6. I ran SFCFix.exe. It says SURT total detected corruption count: 1535, and fixed nothing
, the log is also attached.
About the Windows version I'm using - I bought a legit copy of Windows 7 pro years ago off Microsoft, and for some reason I upgraded to Ultimate within the OS. And I had to use a certain program to activate/crack it. I don't have problems installing other updates, no black screens. Just having problems with the KB3126587 and the never-ending update of the oldest IE 11 version.