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Seagate DiskWizard/Maxblast - you must have at least 1 Seagate/Maxtor drive. You can make backup images of drives/ partitions manually. There is no scheduling. There is no file/folder backup. I found it large and heavy on resources - but hey, it's free.
Macrium Reflect Free Edition. Images Drives / partitions - allows scheduling , mounting and restoring individual files from the mounted image. There is no separate separate file/folder backup with the Free Editon. Extremely small, fast relatively light - I have found it totally reliable.
Paragon do free Drive Backup Express version on their website - does a good job and is reliable - but very limited features.