Hmm, not sure what could be causing that. If the installer doesn’t work then one option would be to use the ZIP files available for each build on GitHub. Make sure you’re logged in to GitHub, click the latest successful build, scroll down to Artifacts and take for example the “Tiled-win64” (without the .msi extension).
It could be useful to provide ZIP archives on itch.io as well, especially since the itch.io app also prefers that, but in the installation experience seems to be better on Windows with the installer (except for such issues…).