fix

com.microsoft.z3/src/com/microsoft/z3/AF3z3Activator.java

@@ -39,7 +39,6 @@ public class AF3z3Activator extends Plugin {
 		if(System.getProperty("os.name").contains("Windows")) {
 			is64bit = (getenv("ProgramFiles(x86)") != null);
 			prefix = "lib";
-
 		} else {
 			is64bit = (getProperty("os.arch").indexOf("64") != -1);
 		}
@@ -63,7 +62,7 @@ public class AF3z3Activator extends Plugin {
 			loadPluginLocalLibrary(getBundle(), path, lib4, "libz3");
 		}
 
-		if(is64bit) {
+		if(is64bit && prefix.equals("lib")) {
 			// load necessary windows 32 bit libraries
 			String lib1, lib2, lib3, lib4;
 			lib1 = "Microsoft.Z3";