diff --git a/src/SMESH_I/SMESH_Gen_i.cxx b/src/SMESH_I/SMESH_Gen_i.cxx
index 420ce7a7c..0823b3314 100644
--- a/src/SMESH_I/SMESH_Gen_i.cxx
+++ b/src/SMESH_I/SMESH_Gen_i.cxx
@@ -321,7 +321,7 @@ SMESH::SMESH_Hypothesis_ptr SMESH_Gen_i::createHypothesis(const char* theHypName
     aPlatformLibName[0] = '\0';
     aPlatformLibName = strcat( aPlatformLibName, "lib" );
     aPlatformLibName = strcat( aPlatformLibName, theLibName );
-    aPlatformLibName = strcat( aPlatformLibName, ".dll" );
+    aPlatformLibName = strcat( aPlatformLibName, ".so" );
 #endif
   }