Dropwizard 0.7.1 used com.sun.jersey:jersey-server:jar:1.18.1, where version 0.8.0 comes with org.glassfish.jersey.core:jersey-server:jar:2.15. Before, when uploading files, it was enough to add the com.sun.jersey.contribs:jersey-multipart dependency like so: <dependency> <groupId>com.sun.jersey.contribs</groupId> <artifactId>jersey-multipart</artifactId> <version>1.18.3</version> </dependency> This will not work anymore and throws the somewhat cryptic exception: java.lang.IllegalArgumentException: The MultiPartConfig instance we expected is not present. Have you registered the MultiPartConfigProvider class? The correct dependency should be <dependency> <groupId>org.glassfish.jersey.media</groupId> <artifactId>jersey-media-multipart</artifactId> <version>2.15</version> </dependency> Update your imports and you’re good to go.