how can I be sure? it just happen sometimes

so can be bios dependent?..it’s possible to change from /dev/sdn to UUIDs…how? Thanks

sorry was ext4…ops

ok, will try Many Thanks!!

I not on that machine but as far as I remember it’s a full ntfs partition, don’t think I ever changed fstab

ok, thank you very much for detailed explanation, yes I remember that I had removed timeout from grub in the past, I will follow your procedure and select previous kernel. Another question, once I’v selected the older kernel did you think that removing (it’s fine using apt?) and resinstall newest kernel will fix the issue or I’v to keep the older kernel? In case I’v to keep the older kernel how can I avoid that it will be overwritten once I update the os?

seems not…but I’m not used to intense task

ok, I’ll backup all data first. How can I remove old kernel without enter in grub menu (since usually boot works well) and select the oldone as default? Thanks