So i fixed this grub problem with Ubutnu boot repair disk located at

http://sourceforge.net/projects/boot-repair-cd/?source=dlp

I’ve download iso image, burn in into my flash using Unetbootin, a then simply boot computer using this flash. After boot process appear new window called “Boot Repair”.

In that window to fix “alloc magic is broken” i click on  button named “Recommended repair”.

After few minutes of repairing problem “alloc magic is broken” solved