You receive the following error on backup or replication processes during VSS guest processing:
0x80042327 or Error: VSSControl: -2147212505
0x80042327 translates to the VSS error “VSS_E_REBOOT_REQUIRED”.
This error is reflecting that the system is pending reboot due to an application installation or due to other processes that place the system into a reboot-pending state. It will be impossible to create a system state backup while this system is in a pending-reboot state, and only a crash-consistent backup may be achieved.
In some instances, you may be able to fool the system into thinking that this will be possible by restarting the Volume Shadow Copy Service. Eventually the system must be restarted, however.