Re: [DependencyError] VIB VFrontDe_bootbank_net51-drivers_1.1.0-1vft.510.0.0.799733 requires vmkapi_2_1_0_0

When you have verified that you dont have a need for net51-drivers anymore you could uninstall it. Place the Host into MM and try

esxcli software vib remove -n net51-drivers

Regards,
Joerg