On Mac OS 10.11.6, I updated to VBox 5.4.2 a while back but didn't get to the additions install until today. I used
http://download.virtualbox.org/virtualb ... ox-extpack to download the extensions pack 5.4.2 and attempted to install it. I got this error on the install:
Failed to install the Extension Pack /Users/MyUserName/Downloads/Oracle_VM_VirtualBox_Extension_Pack-5.2.4-119785.vbox-extpack.
Failed to load the main module ('/Applications/VirtualBox.app/Contents/MacOS/ExtensionPacks/Oracle_VM_VirtualBox_Extension_Pack/darwin.amd64/VBoxPuelMain.dylib'): VERR_FILE_NOT_FOUND - dlopen(/Applications/VirtualBox.app/Contents/MacOS/ExtensionPacks/Oracle_VM_VirtualBox_Extension_Pack/darwin.amd64/VBoxPuelMain.dylib, 6): Library not loaded: /Applications/VirtualBox.app/Contents/MacOS/VBoxVMM.dylib
Referenced from: /Applications/VirtualBox.app/Contents/MacOS/ExtensionPacks/Oracle_VM_VirtualBox_Extension_Pack/darwin.amd64/VBoxPuelMain.dylib
Reason: Incompatible library version: VBoxPuelMain.dylib requires version 5.2.4 or later, but VBoxVMM.dylib provides version 5.1.30.
Result Code: NS_ERROR_FAILURE (0x80004005)
Component: ExtPackManagerWrap
Interface: IExtPackManager {edba9d10-45d8-b440-1712-46ac0c9bc4c5}
and when I tried to reopen my VBox to recapture the screen that reminded me about the new extension pack, I get this error:
Failed to open a session for the virtual machine Windows 7.
Implementation of the USB 2.0 controller not found!
Because the USB 2.0 controller state is part of the saved VM state, the VM cannot be started. To fix this problem, either install the 'Oracle VM VirtualBox Extension Pack' or disable USB 2.0 support in the VM settings.
Note! This error could also mean that an incompatible version of the 'Oracle VM VirtualBox Extension Pack' is installed (VERR_NOT_FOUND).
Result Code: NS_ERROR_FAILURE (0x80004005)
Component: ConsoleWrap
Interface: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}
Help!