virtualbox-ose 2.1.0: Failed to open/create the internal network

Thank you for your bug report and for pointing at the possible solution; I've found that during the merge already and it should have worked.
In fact, for me vboxnetflt was still working - but only since I've manually installed the do_Module.symvers file and the module has not been removed when uninstalling/reinstalling virtualbox-ose-source (and therefore it was still working for me later).
Both should be fixed in the next upload.

This bug was fixed in the package virtualbox-ose - 2.1.0-dfsg-1ubuntu2~blueyedppa1

---------------
virtualbox-ose (2.1.0-dfsg-1ubuntu2~blueyedppa1) jaunty; urgency=low

  * Remove vboxnetflt dkms module in virtualbox-ose-source.prerm
  * Make script used for DKMS "interlinking" executable, so DKMS
    executes it (LP: #314650)
    - debian/rules

 -- Daniel Hahler <email address hidden> Wed, 07 Jan 2009 20:27:10 +0100

this bug has reappeared in lucid,
when i switched from nat networking adapter to bridged
this happened on every startup of the machine i see this error

Failed to start the virtual machine wondowz.
Failed to open/create the internal network 'HostInterfaceNetworking-wlan0' (you might need to modprobe vboxnetflt to make it accessible) (VERR_SUPDRV_COMPONENT_NOT_FOUND).
Failed to attach the network LUN (VERR_SUPDRV_COMPONENT_NOT_FOUND).
Please install the virtualbox-ose-dkms package and execute 'modprobe vboxdrv' as root (VERR_SUPDRV_COMPONENT_NOT_FOUND).
Result Code:
NS_ERROR_FAILURE (0x80004005)
Component:
Console
Interface:
IConsole {6375231a-c17c-464b-92cb-ae9e128d71c3}
__________________
in the console

travis@travis-laptop:~$ modprobe vboxdrv
travis@travis-laptop:~$ sudo modprobe vboxdrv
[sudo] password for travis:
travis@travis-laptop:~$ modprobe vboxnetflt
FATAL: Error inserting vboxnetflt (/lib/modules/2.6.32-16-generic/updates/dkms/vboxnetflt.ko): Operation not permitted
travis@travis-laptop:~$ sudo modprobe vboxnetflt
FATAL: Error inserting vboxnetflt (/lib/modules/2.6.32-16-generic/updates/dkms/vboxnetflt.ko): Invalid module format
travis@travis-laptop:~$

i went into synaptec and reinstalled virtualbox-ose-dkms
then got the same result in terminal and vbox

let me know if there is any more info that can help

I'm also experiencing this in Lucid.

Virtualbox message: Failed to open/create the internal network 'HostInterfaceNetworking-wlan0' (you might need to modprobe vboxnetflt to make it accessible) (VERR_SUPDRV_COMPONENT_NOT_FOUND).

sudo modprobe vboxnetflt: FATAL: Error inserting vboxnetflt (/lib/modules/2.6.32-21-generic-pae/updates/dkms/vboxnetflt.ko): Invalid module format

...and finally I can get it working with:
sudo insmod /lib/modules/2.6.32-21-generic-pae/updates/dkms/vboxnetflt.ko

Maybe the modprobe calls in /etc/init.d/virtualbox-ose need to be changed to insmod calls?

I've opened a new bug instead of continuing to comment on this one, even though it's the same problem, as this one has been marked "fix released".

Networking doesn't work because modprobe vboxnetflt fails:
https://bugs.launchpad.net/ubuntu/+source/virtualbox-ose/+bug/571574