I have restored my Windows 10 installation (v. 1803) 64 bits (from Windows settings>restore, only preserving Windows configuration).

After that, I have installed Inkscape 92.3, but now there is no way to associate svg files with Inkscape. I have tried every possible solution I have found on the web, including this forum, without any luck. By default, Win 10 associate svg files with IExplorer. I can change the association to Chrome browser, Edge browser, etc. But when I try with Inkscape it continues with IExplorer or the other browsers.

Then, I unistalled IExplorer from Windows options, and now svg files haven't a default associated program but I continue not being able to change to Inkscape.

Any help would be appreciated

This bug report will give you a way to do it. If I recall correctly, it's ultimately a Windows bug. But if you delete the registry key which is explained in the bug, the association should go right through. I've had to do that on 3 different versions of Inkscape now. So tired of it, but will soon be starting to switch over to Linux anyway.

https://bugs.launchpad.net/inkscape/+bug/1417146

No. As I said, I have tried all these solutions I have found online, but no one functions. As a matter of fact, I have had to install IExplorer again, because deactivating it broke links in Outlook messages!

To quote from the above referenced bug report:

To manually work around it:
- Open "regedit.exe"
- Browse to "HKEY_CLASSES_ROOT\Applications\inkscape.exe"
- Delete this key ("inkscape.exe")

Afterwards you should be able to associate SVG files with Inkscape normally.

Are you saying you followed those steps, and you still can't associate SVG to Inkscape? I don't think those instructions appear anywhere else, except for this bug report. At least at the time I posted the report originally, they didn't appear anywhere else. Maybe they do by now, I don't know.

Anyway, if those steps don't work, you might have a slightly different problem.

There are somewhat similar issues discussed in Comments #6 through #11 of that same report, which I suppose might help you. I don't clearly understand them, but you might.

If those don't help either, I would suggest to take it to developers (Inkscape developers rarely visit forums). You can reach developers through mailing list, IRC, or new bug report, if you think you found a new bug. Info here: https://inkscape.org/community/. And here: https://inkscape.org/contribute/report-bugs/

If you discover that yours is a different problem from that bug report, will you please post that info here, so that others can benefit from what you learn?

Yes, indeed. I followed this and other suggestions, and no one of then works in my case, so I see it isn't an easy problem.
I am thinking to make soon a clean reinstall of Windows 10, so I am going to wait, hoping this will solve the problem.
In any case, thank very much for your help.