this is a great lesson in back up.
not just because it could be sonar or things along these lines but I back up everything not just my digital audio files.
my word doc, photoshop docs, exc.
 
I know its not what you want to hear but hopefully we live and learn :)
 
good luck.

No need to kill, you just need to Back-Up!
 
If i work on a project for 30 seconds or for 3 months, i always back it up after each time i opened it and change it. Sooner or later, a project will get corrupted, its just a matter of time. Computers and digital audio is not flawless. 
 
You should actually have 3 copies of every project and i copy kept off site, in case of fire or theft and the other copy on another hard drive (external or internal). This will save you from this happening again, and it will happen again!!
 
I'm sorry to hear your troubles, and i'm sure you will start backing up now, as this is a hard lesson learned.
 
Hopefully others will read this and learn from your situation

First of all.... all may not be lost.  Read on down a bit, as I think this happened to me and I was able to recover the project with minor loss to the tracks and latest edits.
 
....when recording.......  save the projects often.  ALWAYS!!  Click on the SAVE icon, I don't use autosave.
 
Never have 2 different songs in the same project. Always have each song in it's own unique project. You can use any common CD burner program later to put the songs into a CD project in whatever order you want.
 
I would try one other thing before spending all that time to rework the 45 minutes of music...... it's worth a try.
 
Do a System Restore to a restore point before the crash of the project. You might be pleasantly surprised to see the project is not a total loss. I think I used this to recover a project that crashed in the very same manner you described. You will of course lose the latest tracks you recorded but the project will be (should be) there.
 
If you do manage to recover it.... save it first, then split that sucker up into it's individual parts and learn the lesson from this.

I had the same issue some month ago and managed to open the project with Sonar 8.5.
A vst fx .........
 
Good luck
Pragi
P.S. The headline reminds me of Black Sabbaths:
Killing yourself to life!

If you can use system restore to recover a shadow copy of the file, you should also be able to right click and choose properties... Then restore previous version.

This only works if you have set the drive up for it.

 
Wot, no back-ups ?
 
Smart-arse humour aside, the way you are working there with all your songs in one project is kind of asking for trouble, especially without a back-up, Not what you want to hear maybe, but just seems an odd thing to do. Hope you manage to find an easier way out than re-creating, but you really need to change the way you work.

I often mix a whole nite in one project, but I am careful with backups. So, not a big deal for me to have thirty songs in one project. I'm just telling you so you don't feel alone.

I too am a bit puzzled that you would still be trying to record parts in a multi song project.  Usually you'd finish all track recording in every individual song and then import all ten in for mastering.  In any case, I wish you luck and, like others have said, make more versioned backups in future.
 

The strange thing is that I had some backup (3) made by the auto-save feature (which I'll disable, since I save every 30 seconds, no jokes) but since they are so close in time (10 minutes between each) the project was already half corrupted and I could not open the oldest one.
 
Anyway, I'll think about a new way to backup my files more often, probably abusing the "save as" function.
 
The reason why I lay all the songs back to back is because once I playback the whole project, I mix one time and have consistency through all songs, instead of always having to copy the settings from song to song, or delete, save as and paste the new song into the "mixed" project etc.
 
It work like playing a mix from a tape multi-tracker and mixing through a hardware console, with all basic effects applyied. I love this seriously.
 
So, to avoid confusion in Sonar, I discovered that bouncing the clips parts to complete tracks make it MUCH easier for Sonar to handle. So here is what I'll do:
 
1. Create a project named "Song1" (whatever)
2. Once Song1 is finished (backup to taste while recording....), save as "Song2" and  bounce every clips togheter 
3. Finish "Song2", save as "Song3", bounce to clip
4. Repeat until the end of times, or 'till the end of the album, whichever come first
 
So this way you always have a copy of the song in "take format" in case you bounced it without noticing some mistakes or need to revert the bouncing operation for whatever reason.
 
I did this in 2010 (been a while I haven't recorded... this can explain my super-fail here) with a 60 minutes/72 tracks album on a intel E5200 core 2 duo at 2.5ghz with 2 gb of ram on a 5200rpm HDD with Sonar Studio 8... and it was running smoothly (everything bounced, nothing freezed), so let's just say that today's machines are more than up to the task.
 
Too bad I can't use system recovery because of "system optimisation for DAW"... anyway, I'm sure that the remake will be even better! 
 
Thanks for your help all, and seriously, all tracks on the same project, when used WISELY, is really nice to mix 

I would work on SONG1 and finish it. Save it as song1a or song1b for the various versions..... be careful with saving multiple copies since it will quickly fill up a hard drive with duplicate audio files.... If you have a 1GB project file.... (not impossible in audio recordings) and have 4 different complete project versions saved..... man you are wasting over 3GB of space on one song..... multiply that by 10 songs and you have 30GB of wasted space on the drive. Trust me, those huge drives WILL fill up faster than you thought was possible.
 
After finishing with SONG1d, or whatever version is the final.... delete ALL the other older non-accepted versions and their associated files. (house cleaning)
 
Now.... if you want to keep the same settings and such in the project..... simply open the project for song1d and delete all the track midi and audio data..... leave the FX and vst's and busses in place.... then SAVE IT as SONG2a....
 
Now record the next song in the project. Your settings are exact to the first song, but you have it in a new project folder so disaster will not destroy the entire project.
 
 
Yes.... on the SAVE..... I save manually. I save after every recording of a clip.... or a punch....or an edit. I save after every musical phrase as I work through the edits on a vocal fix with melodyne.... I save after I make a slice and dice/copy paste edit that worked as I wanted it to work..... I save often, and I save manually.  My system is generally rock solid. I have very few crashes or glitches, but they will occur none the less, simply because it's WINDOWS, so yes.... I save often.