Importing MT 3.16

I’m trying to import my posts from Movable Type version 3.16 I followed the instructions from the admin panel and exported the MT files as mt-export.txt file, uploaded it to the /wp-content/ directory, then clicked the “Import mt-export.txt” button on the admin panel.

It said that the files had been uploaded and gave me the “have fun” message, but when I view the page the imported posts don’t show up. What did I do wrong? Or is this version of MT too old to be compatible?

Thanks!