Sometimes it’s possible (though very rare) that you’re cloning a site from one server to another, and unfortunately the two MySQL servers involved have a mutual incompatibility which your site built on top of, in the area of character sets. i.e. Your WP install was installed (as I say, this is rare) to not use a default MySQL character set, and the destination server does not support the choice that was made.
In this situation, currently, running a database restore will not work.
In our next release, we now handle this better. The database is pre-scanned for the character sets used, and the destination server is checked to see what it supports. If there’s an incompatibility, you will be told, and given the choice to either stop (so that you can ask your server admin to add support, or perhaps upgrade MySQL), or to just import the table using a different character set (which can work, as long as the data in the table didn’t use any of the exotic/missing characters from your chosen character set. UpdraftPlus will choose the character set whose name most closely matches the wanted one, which is usually the best option of those available).
So in summary: better handling of an awkward/difficult situation, giving your more information on what’s going on, and options on how to handle it instead of failure.
David Anderson (lead developer, UpdraftPlus)