Any news about this issue? im getting the same error on MacOS Sierra with VMware-Fusion and Virtualbox.
I do not have VirtualBox installed on my MacBook Pro, yet I am experiencing this issue. Sierra 10.12.4 and Fusion 8.5.6. Any ideas what might be the cause besides VirtualBox?
I too have suffered from this issue for over a year, I've tried every release of Fusion upto 8.5.8 and still the problem persisted.
Amongst the comments in this thread a reference to Fusion 5 - Could not open /dev/vmmon: No such file or directory. was made, this proved invaluable as it hinted at the possible issue,
"It seems that some driver on your system is triggering the problem by consuming all of the available "character device major numbers" (a small number used to identify a driver/device). I can't immediately identify the culprit driver, but the possibilities include:
- Studio Network Solutions iSCSI initiator
- Viscosity VPN
Its reference to Viscosity VPN as possible factor made me consider the VPN tool of choice I have installed, namely SHIMO VPN. As a test in hope I removed this SHIMO VPN tool (a shame as I rely on it) and restarted OSX 10.12.6.
After the reboot I can successfully launch both VMWare Fusion 8.5.8 and VirtualBox 5.1.20 without issue, so my '/dev/vmmon' issue is solved, albeit at the expense of a great VPN tool, SHIMO.
Hope this helps.
Aside: I've contacted SHIMO with this info in the hope they can resolve the issue.
in my case, I solved it by remove tuntap(virtual network interface).
macOS Sierra 10.12.6
- VMware Fusion 8.5.8
- VirtualBox 5.1.28
- tuntap 20150118 <- uninstall you
How to uninstall tuntap
sudo rm -rf /Library/Extensions/tap.kext
sudo rm -rf /Library/Extensions/tun.kext
sudo rm -rf /Library/LaunchDaemons/net.sf.tuntaposx.tap.plist
sudo rm -rf /Library/LaunchDaemons/net.sf.tuntaposx.tun.plist
reboot your mac.
Now I can run VMware Fusion and VirtualBox together.
I had the same error with Fusion and VirtualBox, I installed the oldest version of VirtualBox that I coud find, got the VMs working then upgraded to latest version 6 of VIrtual Box.
Perhaps installing a very much older compatible version of Fusion/Workstation will fix the same. Shame Fusion support have offered nothing at all for weeks and months on this one.
It turns out that VMWare and VirtualBox can't co-exist or at least their kernel extensions can't be running at the same time. The following manual workaround works for me, I'm on the latest macOS and VMWare and VirtualBox versions as on 2019/01/30: https://kastelo.net/blog/2017-05/coexisting-virtualbox-vmware-fusion-macos/