All foreign characters have been replaced by "????"

Question

While switching webhosts, I downloaded the MySQL database and reuploaded it to another webhost. All of the foreign characters on my site have been replaced by question marks. 

For example, see: http://wikitranslation.org/?qa=%3F%3F-english

How can I fix this problem?

Answer 1

I have fixed the problem. Lesson learned: always use phpMyAdmin to export databases, and not whatever dumps the hosting company provides.