Crikey, Ian, I saw the subject header and thought it was going to be a spam post :)

Well, now, there's a thing i've tried.

I can't remember what software I tried, but, yes, the one I used did suggest a number of tweaks to Windows.
Did it make any difference to me? The answer was, no, it didn't. That's probably because I did carry our frequent maintenance on my system.
Why did I try it? Because I was interested in the claims.
I'm sure the best ones do make a difference to those that do nothing to their system.

Did it make any difference to me? The answer was, no, it didn't.

Yes well after I made the post I looked into some trusted forums I have used in the past to look for leads/recommendations.

Ditto same results as yourself.

Then I remembered I had Ashampoo Win Optimiser which I paid for and have had for yonks, mainly only used to clean up drives. Gave it a try on "OneClick" which got it all excited about - probably fixed a few things but not the Sfc /Scannow message:

Windows Resource Protection Could Not Perform The Requested Operation

I was getting stupid restarts so a week ago I reinstalled Windows 10 which is a monster pain in the backside. Went alright for a few days then the odd gremlin. Anyway I'll live with it for the present.

As an aside - purely as another useful tool - I finally built myself a working WINDOWS TO GO USB drive. It actually works but the newer USB drive I purchased cracks me up by its miniature size. It's hiding at the back of my desktop in the only USB-C socket I have.

USB Drive Kingston 3.2 DataTraveler 80 32GB Type C Flash Drive - Google to see the physical size.

I got a special deal on eBay where I now get random rebates - cost me $A12.95 [after $5 rebate] including next day express postage.

Had to use an earlier version of Rufus. I used Rufus 2.18 later versions don't work. And of course I have ISO's galore I download as ESD's.

Miniature Win 10 Operating system on a USB the size of some postage stamps - remarkable.

[Minor Edit]

Restarting Windows first thing this morning? You guessed it... probably even more problems than before.

Being the undaunted type of person I decided to properly road test my new WINDOWS TO GO USB.

As most of my programs have always resided on drive W [unaffected] for years and other items are also divorced from drive C - now only 32 Gb in size, I was able to motor along today with the minimum of adjustments.

See I can even easily speak to you right now. Having profile backups for programs like Firefox, Thunderbird etc really help and Chrome does its own thing with Google when I log in there.

I'll investigate Win 10 on the 240 Gb SSD later in the week. Today I'm sick of Windows today so I'll just read my Sunday Online papers and my preferred cartoons.

My fix to these Window 10 Pro start problems? Restarts obediently so far now.

Bludgeoned the whole thing into going to the Windows Repair Disc I put in the DVD drive - which Mr. Windows never made as a bootable version when I created it back in my complete rebuild last August.

Don't ask me why because I don't know. I can faithfully, and truthfully attest that this is the FIRST AND ONLY time a Windows repair disc was ever a help. None since DOS 3 have ever worked for me...

Oh!

And what might have caused all these problems? Downloading a whole truckload of updates a few days back....

Maybe/Possibly/Perhaps/ or I dunno...

Hmmm spoke too soon. Tried Sfc /Scannow and message still remains:

Windows Resource Protection Could Not Perform The Requested Operation

I'll just continue to mosey along...

Oh my, you've got my sympathy.

I do know what it's like having problems with Windows, and it can be a nightmare. Having been a Windows user since the start i've seen all kinds of problems over the years, and I have found so-called recovery disks to be variable in efficacy.

I've moved, in part, to Linux for some tasks, but remained with Windows on others.

I'm convinced that MS do not develop for the weakest system, and are in cahoots with the hardware vendors to help drive sales.

I only have one solution for you, and that's to ditch the current hardware on Windows and install Linux, and to buy new hardware for Windows. </ducks>

Brand new hardware last November,

New AsRock Mobo, New 16 Gb RAM, New SSD 240 Gb, New Intel CPU, same case, same fans, reinstall Windows 10 all over again.

Cuppla new HDD - One new 1 Tb partitioned for W,X, and Y drives. Two 3 Tb and one 4 Tb drive. Retire a cuppla others.

Linux? Tried that years back and found it too arcane - bad enough when I had to learn machine hand coding for Motorola microcontrollers, and Rockwell CPU's in the late 1970's - that was bit, by bit literally. Start by setting a stack of [hex] 100, then clear all registers.... yadda yadda...

Next year I turn 80, I'm tired of learning. From age 17 to 52 I spent almost half that life time at colleges, universities becoming this, becoming that...

Thanks for the thoughts Neil.

Now about 7.30 pm local - bed time. My cat told me so...

Ahhh, new hardware already, fair enough.

It's odd that it is giving you grief, unless, perhaps, there's a corruption on the drive.

There is always that OTHER method:

System Restore: Pick a date, as far back as you can go, to when the system last worked properly.

Let system restore do it's thing, then, after reboot, let THAT version find all the new hardware, etc, and see what happens.

perhaps, there's a corruption on the drive.

No. It is a brand new SSD and I had every SSD, every HDD and every USB checked over by each manufacturers tools.

Samsung, Seagate, Western Digital - all pass with flying colours - and yes each also passed their competitors drives.

System Restore: Pick a date, as far back as you can go

Another thing I haven't enjoyed a great deal of success with.

I did try a different program called FixWin 10.2.2 that is built by The Windows Club [no personal connection] and it is completely free. I had it fix a few things and have had several successful restarts. Could be worth looking at if anyone else is having problems.

Everything is now going just fine except SFC /Scannow still produces the same message. I recollect similar messages with DISM years ago.

You know what I think? I now think it both SFC, and DISM which are a problem in themselves...

For now as it all works I will leave well enough alone.

Thanks for the input folks.
[Edit] Clarity