Extension Pack installation fails for 4.2.1 on MacOS

[Mark Scarton]

I just downloaded and installed the latest release of VirtualBox for MacOS, 4.2.1. But when I attempted to install the extension pack from 4.2, it fails with the following error message. It looks like 4.2.1 may have been packaged with a back level release of a support library.

    Failed to install the Extension Pack /Users/X/Downloads/Oracle_VM_VirtualBox_Extension_Pack-4.2.0-80737.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 4.2.0 or later, but VBoxVMM.dylib provides version 4.1.23.

    Result Code: NS_ERROR_FAILURE (0x80004005)
    Component: ExtPackManager
    Interface: IExtPackManager {3295e6ce-b051-47b2-9514-2c588bfe7554}

[Frank Mehnert]

No, it rather looks like you installed VBox 4.1.23 but are trying to use it together with the 4.2.1 extension pack. What does the 'About VirtualBox...' screen say?

[Mark Scarton]

Well, that's embarrassing. I was pointing at the wrong installer. You're absolutely correct.

My apologies for wasting your time.

Thanks! Mark