On Fri, Oct 11, 2024 at 1:31 PM I wrote:
 Short story: with the next release, 2024c, we plan to make substantial
 changes to our 64-bit Windows build (though mostly they will not be
 very visible to users) and we'd like to get as many people as possible
 to give the new build a try in advance of the release (currently
 slated for the week beginning October 21).
 As of later today, the snapshot on sourceforge labeled
 gretl_install-64.exe will be the NEW build. 
P.S. Sorry, I should have said this before. If you have been using the
"old" build of gretl for 64-bit Windows and want to try the new one,
we recommend uninstalling the old one first. If you don't uninstall
the old version you'll end up with several redundant DLLs pertaining
to GTK2 in the gretl directory under Program Files.
Allin Cottrell