View source for Horror - I lost 10 years of my work

= Question =

''Przemek asked: '' 

'''After a hard disk failure, 10 years of my work with SuperMemo seems to be gone!'''

In August I had some problems with my computer (it used to crash a lot) so I didn't install the newest version. In mid August, I took my computer to my computer shop Komputronik (the computer is still under warranty). 
However, they didn't manage to look at it in August. In September they told me at Komputronik that my old hard drive broke up and that when they took it out the computer is fine. I used to have two hard drives (the old one taken from my previous computer and the new one still in the computer). I thought that I was working on the new drive with a copy on the old drive (because I was clicking on the Advanced English icon on the new drive). 
However, now when I click on the same icon when the old disk is out I cannot start SuperMemo. 
What can I do to get it work again? Could you please help me? It's 10 years of my work.

= Hints = 

It is not clear from your description if it is SuperMemo missing (you can always download it again) or if these are your collections (only you can now find them on your backup disks, assuming you have any!).

# To find your supermemo see: http://www.supermemo.com/help/inst.htm#Where
# To get a replacement of your SuperMemo, write to SHOP AT SUPERMEMO COM
# To find your collections, search all your hard drives for files with the extension KNO (before you open these, create a new backup, just in case the old one was incomplete or damaged)
# To find out what is hiding behind your SuperMemo icon, right-click and choose '''Properties'''. It might hold a collection (e.g. D:\sm8\systems\AE1997.Kno)(bad news) or SuperMemo itself (e.g. D:\sm2006\sm2006.exe)(good news)

'''Vital Lesson:''' Do not trust any media! Always keep backup copies on DVD-Rs, flashdrives, hard drives, neighboring networks and at different locations than your home or work! If you keep several copies at one location, you can lose them to flooding or fire. If you keep them on a single hard disk, you WILL LOSE THEM ALL one day.

(the most optimistic scenario is that your drive letters changed and all your collections are ok, but you still should use the occasion to rethink you backup strategy)


= From another Supermemo User =

Do you still possess the old harddrive, or if not, can you obtain it from the shop that 'repaired' your computer? If you do, there are many companies that specialize in recovering data from seemingly unrecoverable HDD failures. Just do a google search for these, and choose a specialist with lots of references! 

Note that some of these companies may charge a high price, but if it was me, and I was in danger of losing 10 years worth of SM data, then almost any price would be a small price to pay...

= Essential reading =

* '''You need to backup regularly''': http://www.supermemo.com/help/backup.htm
* To learn more about files and backups: http://www.supermemo.com/help/faq/files.htm

= Answer =

When you change computers, drive letters may change. Drive E: may become drive F:, etc. On restart, SuperMemo will search for your collections in the place it was last left. Use '''File : Open collection''' to find your collection in the old location on a newly named drive. That should solve the problem.