Ok i found the solution
There is a bug in the last release
When you enable autoupdate function in the updates menu, it creates a new cron job
but the cron job is fault so crontab exits ..
you have to edit from the cron menu, the job concerning sudo /usr/local/vesta/bin/v-update-sys-vesta-all
Just add a star to the blank field 'day of week'
Restart your cron service ... and all is fine !
Hope it helps ....