java.lang.UnsatisfiedLinkError: could not load i4jinst from C:\Program Files\NeoLoad 5.0\.install4j\i4jinst.dll, true, C:\Program Files\NeoLoad 5.0\platform.zip, false, C:\Program Files\NeoLoad 5.0\i4jinst.dll
at com.install4j.runtime.installer.platform.win32.Common.init(Unknown Source)
at com.install4j.runtime.installer.platform.win32.FolderInfo.<clinit>(Unknown Source)
at com.install4j.api.windows.WinFileSystem.getSpecialFolder(Unknown Source)
at com.neotys.nl.controller.lc.b(lc.java:118)
at com.neotys.nl.controller.lc.a(lc.java:60)
at com.neotys.nl.controller.Controller.db(Controller.java:1514)
at com.neotys.nl.controller.Controller.hb(Controller.java:1554)
at com.neotys.nl.controller.Controller.start(Controller.java:342)
at com.neotys.nl.launcher.ControllerLauncher.main(ControllerLauncher.java:217)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.exe4j.runtime.LauncherEngine.launch(Unknown Source)
at com.exe4j.runtime.WinLauncher.main(Unknown Source)
at com.install4j.runtime.launcher.WinLauncher.main(Unknown Source)
When do you have that error? If it's during the installation phase i would say that your installer file is corrupted.
You should try to download it again from the Neotys web site using a different download protocol HTTP or FTP.