KKB000857
SYMPTOMSBackup log reports "Synthetic Full Backup failed" and "The full file will be transferred. The error received was: ERROR! Unable to open source archive"
CAUSESynthetic full backups are created by consolidating the previous backup set (full plus incrementals). This error occurs if one or more of the files from the previous backup set is no longer found in the image location. It may be because files have been deleted or cannot be access due to a network or hardware fault affecting the image location.
SOLUTIONThe system will automatically create a non-synthetic full backup, but this will increase bandwidth usage by offsite replication. If the problem persists, check whether files are being deleted by a user.
APPLIES TOKaseya Backup