I was working around 9:00 am, checking that there was a bunch of bak files from 7:00 am to 9:00 am because something was wrong and I quit Cubase. But as soon as I quit, the bak files disappeared and I flew all the work for two hours. This behavior of Cubase is not understood.
If Cubase is going to delete the recent bak file by itself, is not the bak function useless? That’s absurd.
I have had the same issue, losing hours of work… Incredibly annoying.
I didn’t have this issue.
Under Prefs\General, check to see what your max amount of backups is set to
Check the auto save interval time as well
Just a couple of ideas. Yeah the backup is wonky in my opinion
Make sure you SAVE before quitting of course
Above all, SAVE often. Im neurotic with saving here
The root cause of this is that if you Close a Project and Cubase asks if you want to save it - and you answer “no” then Cubase assumes you do not want to retain any of the recent changes (i.e. you want the Project like it was on the last Save) and if you don’t want the changes you also do not need the .bak files created while making those changes. ¯_(ツ)_/¯
So it deletes all the .bak files created during a session if you Quit the session without Saving.
The first rule about using computers is that you have to save your work. It’s not neurotic- it’s an excellent habit.
Make your prime directive “Always Save File.” If you use that as the premise for your habits in this area, you will not experience this kind of unpleasant surprise, and there is no requirement that you actually use that file.
Use File>Revert instead of ‘Don’t Save’. That function is meant for this purpose, and its result will not be surprising.
Or, just save your work. The .bak files will be there, and your current work will be there too.
Depending on auto save is like trusting your Tesla’s auto-drive feature to not kill you- and it hardly ever will.
I’ve got into the habit of using CTRL+ALT+S all the time these days. I don’t trust the backup system either. It’s a bit of messy solution but I do it without thinking and I’ve not lost a session in a long time.
I didn’t want to say it 
This… obsessively!!
Hi all
I decided to set up a KC for saving, which is the enter key on the extreme right of the normal windows keyboard where the number pad is.just hit it all the time, don’t think about it any more.
Best Regards, Dave
I ran into this issue before. Here’s a previous discussion: BAK file disappeared after crash - #3 by AllanH-CF - Cubase - Steinberg Forums
Let me just paste in the “solution” I found. I realize that the “exit without saving” could also explain it, but I think it’s worth looking in the actual prefs file “just in case”:
Something similar with missing .bak has been mentioned a few times in various threads. I’ve seen the issue and resolved it for me. I found a non-Ascii character in the UserPreferences.xml file. I removed that, and .bak files are again generated. I’m not sure if Steinberg engineering/support reads these notes; they certainly don’t respond, so you’ll have to search a bit for the answers.
The issue in this thread is not that bak files are not generated, but that they are deleted when hitting “Don’t Save”.
fyi
The solution: make a change to your workflow. For something so critical, why would you not?
I fricken double tap ctrl+alt+s yo
that way if I make changes, it’s only to the second ctrl+alt+s which I can then just regular save.
Then, very so often, like, every 10-20 ctrl+alt+s saves, get this, ready? I do a ctrl+shift+s save, and add a save description addendum to the title telling me what it is I have changed or been working on.
This save protocol, has saved me thousands upon thousands of times.
The .baks have saved me in between my consistent manual saves where there has been a crash or an accident, or something,
I would never rely on .baks so much as to critique their implementation or even consider them or think about them. They are an extra extra safety net to catch an extremely unlikely low percentage chance that my manual backups won’t be sufficient in recovering whatever it is I need, which is %99 foolproof.
I use the format (Song)-(Version)-(Revision).
Say a song called Lucy is saved as Lucy-01, I then ctrl+alt+s and it becomes Lucy-01-01, Lucy-01-02, Lucy-01-03 a.s.o.
If I then make any significant change, I save it as Lucy-02 and ctrl+alt+s it becomes Lucy-02-01.
That way I can go back til the beginning of the song if I so desire, and figure out when it all went to H.
It is a good habit to use the build in Notepad for what the significant change you made was.
If the project gets to big with many many .cpr files. I use the backup function in Cubase to move everything to a fresh folder and only have one project file again.
The old folder I manually move to a NAS with lots of Terabytes free space.
I would have killed for such a feature (making fast copies of a whole song) when I was recording to tape.
None of the tapes are playable today, everything I have recorded digitally I still have a copy of a copy of a copy of.
Plan your recordings, and treat them as treasures.
I do similar but flip the naming around. My Project will be named “Lucy” from start to finish. But along the way it sheds off lots of incremental versions of the Project with names like Lucy-pre-vocal-tracking.cpr etc.
Yeah none of my analog tapes is playable. I dream of someday getting them baked, but realistically that probably won’t happen because of the cost. But thinking about it right now gives me an idea. Generally you can’t bake tapes at home because they need to be at a temp higher than room temp but lower than a home oven will go. But what about Sous Vide the tapes - really tight temp control in small batches? 
Since everyone else is chiming in on backups, I’ll offer my opinion.
The .bak files have one purpose and one purpose only: to allow you to recover from a Cubase crash. If Cubase crashes and you need to recover a version more recent than your latest save, use the .bak file. That’s the answer to the question in the thread title. Since .bak files are only for the purpose of crash recovery, Cubase can and will delete them when you quit.
The subject of doing checkpoint saves during the lifetime of a project is another matter. It’s good practice to save the project at significant milestones while working on a project. Basically, any version that represents a significant milestone in the project, or that you might want to return to, should be check pointed. The problem is: simply saving the cpr is often insufficient for this purpose. You need the audio pool as well. That’s why I would recommend doing a Time Machine backup when you’re at a milestone you want to checkpoint. In other words, when It’s time to do a checkpoint save: : save, duplicate the .cpr to a file name with a meaningful name if necessary, and do a Time Machne backup. It’ll just take a few seconds to do this, but it’s a indispensable way to work.
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