Peter Your suggestion is correct. I correct the expression to
(FLMaterializer materializeFromFileNamed: aFileRefence fullName) Now I get another exception. KeyNotFound: key #'ositive8SmallIntegerClusterJ4Ü1‚ð+–( %?"<9ª6PM¾0d*ÒD ''x!Œ8' not found in SystemDictionary I think this is a compatibility problem between different Fuel versions. Johannes Am 05.08.2017 um 11:13 schrieb PBKResearch <pe...@pbkresearch.co.uk<mailto:pe...@pbkresearch.co.uk>>: Johannes Just a suggestion: FLMaterializer class >>materializeFromFileNamed: requires as argument aFilename, not aFileRefence. Presumably this means the name as a string. This makes sense, because #convertToWithConverter: is the name of a method understood by strings. If your invocation of the materializer includes asFileReference, try again without that. Hope this helps Peter Kenny From: Pharo-users [mailto:pharo-users-boun...@lists.pharo.org] On Behalf Of Johannes Brauer Sent: 04 August 2017 23:56 To: Any question about pharo is welcome <pharo-users@lists.pharo.org<mailto:pharo-users@lists.pharo.org>> Subject: [Pharo-users] problem with FLMaterializer Hi everyone, trying to migrate a Seaside application from Pharo4 to Pharo6 I get a problem with FLMaterializer. An expression like (FLMaterializer materializeFromFileNamed: aFileRefence) results in MessageNotUnderstood: FileReference>>convertToWithConverter: The same file can be materialized in Pharo4 without problems. Johannes