problem in vagrant up ... " authentication failure"

when I do vagrant up in ubuntu .. it gives many

 default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...    default: Warning: Authentication failure. Retrying...ls

Timed out while waiting for the machine to boot. This means thatVagrant was unable to communicate with the guest machine withinthe configured ("config.vm.boot_timeout" value) time period.

If you look above, you should be able to see the error(s) thatVagrant had when attempting to connect to the machine. These errorsare usually good hints as to what may be wrong.

If you're using a custom box, make sure that networking is properlyworking and you're able to connect to the machine. It is a commonproblem that networking isn't setup properly in these boxes.Verify that authentication configurations are also setup properly,as well.

If the box appears to be booting properly, you may want to increasethe timeout ("config.vm.boot_timeout") value.

i tried to destroy the vms anr reinstall it but it still doesn't work