pixelsearch, Here is my hobbyist understanding of the situation. DLLs are "loaded" as required but are not necessarily immediately "unloaded" once the call is over. They remain in memory with an internal counter value showing that the DLL is in use. If the same DLL is called by another process then the same code is used and the counter increased to show that there are now 2 processes using it. If one of these processes "closes" the DLL, then all that happens is that the counter is re