OK, I've updated the screen caps.

Yeah Warbler, that was the point of my post re this topic.

I'm (almost)totally with you re not really looking at my archive all that much, but the images I do keep are all the raw files only.

As I displayed in the last versions of screen shots tho, some jpgs do get through and I'm extra cautious not to remove all jpgs willy nilly!

So it's a bit of a tedious process sometimes.

eg. if I just did a *.jpg search and deleted all images, on that search criterion, all my my kids' images would get deleted too .. as they used to use P&S cameras, or phones or whatever.

So the jpgs I do delete are selectively chosen from my confirmed archive of raw files only.

But I'll confirm that Photo Gallery does in fact add, edit, append and catalog the raw files too, as well as jpg files.

As you can see from my updated screen caps, the images I now searched for are predominantly the NEFs.

yes the raw codec has to be installed for both Windows(file) Explorer and Photo Gallery to see and edit tag data in the raw file.

Note I have had an issue not long ago after I installed Win7 too tho. I reinstalled Nikon's v 1.27 of the NEF codec but prior to my reinsall of Win7, I originally had v1.24.
I'd used Gallery for a few months prior to the Win 7 reinstall with no problems, and played with Canon raw files too to boot.

But after the reinstall and with the latest version of the Nikon codec, I couldn't get ViewNX2 and Gallery to interoperate.
That is, tags were either ViewNX2 or Gallery, but neither would recognise the others.

Much head scratching, and also some testing on my tablet(Win7) and no problem there.
it was just a glitch on this desktop for no reason.
I uninstalled the newer Nikon codec, installed the older codec and all was fine.
On the tablet, the newer codec was also fine.
Just to satisfy my curiosity tho, I reinstalled the later Nikon codec again, and now it's all fine again .. beats me why .. just one of those things.

Win10 and all still good.

In Canon world, I couldn't see anywhere to add tag info into the CR2 files at all. Maybe they have a separate program or something??

All I had at that time was DPP and Photo Gallery. If there is any Canon software to tag images, I just don't know of it .. not that it doesn't exist.

I can't for the life of me find Canon's actual latest raw codec(if someone can post an actual file or link .. it'd be nice). I found a link, but couldn't get the actual file.
Windows has a camera pack, which contains many raw file codecs .. can be used but at the time I loaded it, it was circa 2014 build and hence couldn't recognise the later model cameras(eg. 5Dr or whatever).
Use this Windows camera pack with some caution.

I don't have DPP installed gain as yet(on Win10) so from memory .. if you add tag data in Gallery into a .cr2 file, there was a small info window in DPP which recognised this added tag data too.
I think I only had a few 5DmkIII files to play with .. and one other lonely cr2 of I don't know what camera(it's a sample file from a camera filter conversion company).

Can't find a codec for Sigma's X3F files .. but haven't really tried hard either.
I'll see if I can find some Pentax PEF files .. but this point is moot as it's probably best to shoot in DNG on a Pentax.

And remember this cataloging info isn't for general sharing purposes .. it's simply about 'owning' your own data. Really only relevant and about raw file tagging for the purpose of keeping a tack of your archive.

Even Windows file Explorer can tag jpg files.

OH! and if you have the curiosity, once your raw file codec has been installed and confirmed working properly, you should also have the ability to add tag info on the raw file from within Windows (file) Explorer too.
Rightclick the raw file and select properties.
With the properties window now open, click on the details tab.
Scroll your mouse or cursor over many of the available fields .. such as tag, description, rating .. etc and a small highlighted box may appear. Add data there and you have raw file metadata capability there too.

It can be handy, but not really user friendly as a 'cataloging system'. Just an easy way to do the odd file here and there if required.