If you use Bitdefender anti-virus "2011"(v2010 cause not that problem), that might be the problem that windows services "Microsoft Software Shadow Copy Provider" and "Volume Shadow Copy" not work properly! Even if you start them manually!
Actually the default settings of these services in Windows is not automatic but manual. If they can run properly without obstruction, Backup4all (...) is able to start this services if "copy open files" is enabled in advanced settings of your backup job(s).
If you not enable this option, you can backup without shadow copy. But you are not able to backup open files that are in use by applications eg Firefox, Outlook,...
It does not help if you disable the anti-virus shield of Bitdefender 2011!! At the moment i write this, the only solution is UNinstall Bitdefender 2011 or disable "copy open files".
If you need shadow copy and still want to use Bitdefender, you can replace v2011 with v2010.
Your license key is not a problem normally. A key of Bitdefender is time related, not version related. Of course it is program related.
Here you can download Bitdefender anti-virus std 2010 (...)
http://download.bitdefender.com/windows ... /final/en/
Is you have another license, start here: http://download.bitdefender.com/windows/desktop/
I have forwarded this issue today to Bitdefender, maybe they will fix it???
good luck!