This guide will show you how to check and resolve any USN journal issues on your system reserved partition using the windows file system utility, "fsutil". Windows 7 backup error 0x81000019 - a knol by Yohann Sulaiman
This is often the cause of 0x81000019 errors when making a system image.
If this isn't the problem then you need to consider one of:
1) increasing the size of system reserved
2) remove system reserved and include its booting functions in the OS partition
3) use other 3rd party imaging software like Macrium Reflect.