If you are having issues with Acronis Backup and Recovery 11.5 and Windows SBS 2011 or Windows 2008 (including R2), it might be related to your hard drive.
Take a look at this page for the support hard drive on Windows :
First thing you realize is that 4K (4096 bytes) per sector is not supported on every version of windows.
Before buying a new hard drive, you might want to make sure that it is 512 bytes per sector.
Hope I was able to save you some time.