Hello, I already copied the dll to the bin folder of my application. The problem occurs in my 32-bit Classlibrary. -- View this message in context: http://osgeo-org.1803224.n2.nabble.com/MapGuide-2011-64-bit-with-a-32-bit-Application-tp6215511p6215648.html Sent from the MapGuide Users mailing list archive at Nabble.com.