When one deploys an image one usually requires ONLY the image - not the source or changes file. An "image locker" code would look like this: SmalltalkImage checkSourcesFileAvailability: false. SmalltalkImage checkChangesFileAvailability: false do disable acording warnings when source/changefile is removed. If one uses NativeBoost in such a deployment scenario, for instance the NBWin32Shell shellBrowse: 'http://www.google.de' functionality the internal code (due to missing source) now looks like this shellExecute: t1 file: t2 parameters: t3 directory: t4 show: t5 <primitive: 'primitiveNativeCall' module: 'NativeBoostPlugin'> ^ self nbCall: #(#HINSTANCE #ShellExecuteA #(0 #, #LPCTSTR #lpOperation #, #LPCTSTR #lpFile #, #LPCTSTR #lpParameters #, #LPCTSTR #lpDirectory #, #INT #nShowCmd ) ) module: 'Shell32.dll' Hence the t1 ... t5 parameters. NativeBoost is in this situation not able to match the FFI parameters and throws an error "Could not find accessor for variable ..." Try yourself without a changes and source file. This makes NativeBoost not very deployment friendly and unusable in such a "minimal deployment" scenario ... Any comments? Thanks T.