VirtualBox 7 Extension Pack installation helper version mismatch error

[JiF_Brodeur]

Hi, after upgrading to VB7, I tried installing the extensions pack on my Intel mac, macOS Monterey 12.6, I got an error message VBoxExtPackRegister returned VERR_VERSION_MISMATCH ErrInfo=Helper version mismatch expected 0x30000 got 0x50000 result code NS_ERROR_FAILURE (0X8004005) component ExtPackManagerWrap
THanks for your help
Jean-François Brodeur

[JiF_Brodeur]

I found what the issue was, there were previous version of kernel extension left. You can check it by running the following command:
kextstat | grep -v com.apple
Executing: /usr/bin/kmutil showloaded
No variant specified, falling back to release
Index Refs Address Size Wired Name (Version) UUID <Linked Against>
203 3 0xffffff7f9a334000 0xb8000 0xb8000 org.virtualbox.kext.VBoxDrv (6.1.38) 2B6C3D21-B581-315B-B001-5C1AF9D0563B <9 7 6 3 1>
208 0 0xffffff7f9a418000 0x5000 0x5000 org.virtualbox.kext.VBoxUSB (6.1.38) 2E74F524-F984-3FB6-8582-19B9F659A3E2 <207 203 66 9 7 6 3 1>
209 0 0xffffff7f9a413000 0x4000 0x4000 org.virtualbox.kext.VBoxNetFlt (6.1.38) CDFE9449-0CDC-3C9E-A36D-DD7AFD5B9F3A <203 9 7 6 3 1>
212 0 0xffffff7f9a40d000 0x2000 0x2000 org.virtualbox.kext.VBoxNetAdp (6.1.38) 916DA4A8-5017-3987-B55F-8A873B64CE04 <203 7 6 1>
The version number in brackets was a good hint something was wrong, also the documentation mentionned that VBox 7 does not rely on kernel extension any more.
I downloaded the same version .dmg from the web site and ran the VirtualBox-Uninstall.tool see url: https://www.drbuho.com/how-to/uninstall-virtualbox-mac
I re-installed VB7 and extension pack no error.
I think that the original VB7 install left some remnant of the previous version.
Thanks
Jean-François

[YadinF]

6 months later and Oracle has not fixed this bug. Thank you for the solution, worked great.

[LucaJones]

It seems like the issue was due to remnants of a previous virtualbox version's kernel extension.
Running the uninstall tool and reinstalling virtualbox 7 resolved the extension pack installation error.

[scottgus1]

Luca's post is a good condensation of OP JiF_Brodeur's solution. Kudos to JiF_Brodeur for keeping up the hunt!

Yadin, this isn't a bug. It's a difference in operation. When siwtching main versions, it's recommended to uninstall the old Virtualbox before installing the new one.