Aug 06 2017
Microsoft Azure Backup failed to access the shadow copy because of inadequate disk space on the volume. Retry the operation after increasing the free space available in the volume (0x08174).
Feb 28 2018
I have same issue while backing up. FYI i have already excluded following files from antivirus
C:\Program Files\Microsoft Azure Recovery Services Agent\bin\cbengine.exe
C:\Program Files\Microsoft Azure Recovery Services Agent\scratch\*
And I have almost 1.3 TB available space in my c drive.