Backup Options
Open More options on the backup plan page to choose how much history to keep, set a password, and enable validation. The format and compression options also contain file names, backup technology, exclusions, and report settings.
Backup History
Choose How much backup history do you want to keep? to control which versions remain available for restore.
| Choice | Versions kept |
|---|---|
| 1 week | Daily versions for seven days with backups. |
| 1 month | Daily versions for seven days, plus weekly versions for four weeks with backups. |
| 3 months | Daily and weekly versions as above, plus monthly versions for three months with backups. |
| 1 year | Daily and weekly versions as above, plus monthly versions for twelve months with backups. |
| Keep everything | No automatic deletion. You manage the available space yourself. |
| Custom | Your own daily, weekly, monthly, and yearly history, a fixed number of versions, or no automatic deletion. |
History uses periods in which backups actually ran. Time spent with the PC switched off does not by itself erase the history. The presets also keep at least the three newest versions. Older files needed by a retained version remain available, so the number of files on disk can exceed the number of restore points you selected.
The estimated storage requirement helps you choose a history that fits the destination. It is an estimate, not a reservation of space. If space is tight, choose a shorter history or another destination.
Open the backup's history to see why versions are kept and which are due for removal. You can keep individual versions permanently. After successful scheduled backups, the background service removes eligible old versions even when the main application is closed. Existing plans retain their previous retention rules until you change them.
Backup Method
| Method | What is stored | Files needed for restore |
|---|---|---|
| Full | All selected data on every run. | That full backup. |
| Incremental | Changes since the previous backup, after an initial full backup. | The full backup and every required incremental version up to the selected one. |
| Differential | Changes since the last full backup. | The full backup and the selected differential version. |
The automatic method uses incremental backups between regular full backups. In Custom, choose the method yourself if you need differential backups or full backups only.
New Full Backups
With the automatic method, a one-week history starts a new full backup on the first run of each week. Longer presets start one on the first run of each month. These settings choose the backup method; they do not create extra scheduled runs.
Custom settings can start a new full backup weekly, monthly, after a chosen number of change backups, or only when a usable full backup is needed. A weekday-specific backup method in the schedule applies only when you choose the method yourself.
Make this a full backup starts a new chain for one run without changing the plan's usual method. A full backup may also be required after changing sources or when the previous backup cannot be used. The report explains the reason.
Backup Technology
| Technology | Meaning |
|---|---|
| Used sectors | Copies sectors containing data. Suitable for ordinary backups. |
| Forensic | Copies the entire source, including unused sectors. |
| Direct forensic | Reads directly from the disk; available in the recovery environment. |
Forensic images need space for the full source size, rather than just its used data.
Backup Format
The O&O DiskImage format supports the normal backup options, including compression, encryption, and change backups. Use it to back up the running Windows system.
VHD and VHDX are Microsoft virtual disk formats. O&O DiskImage supports whole-disk backup and restore, mounting, validation, and browsing supported virtual disks, including Hyper-V checkpoints (.avhd and .avhdx). Keep a checkpoint's parent files available.
VHD/VHDX creation uses full backups and used sectors, without O&O compression or password encryption. Source volumes must be available for exclusive access, the destination must be on another physical disk, and the disk containing the running Windows installation cannot be captured this way. Close applications using the source or use the O&O DiskImage format for a live backup. The plan page explains unsuitable source selections.
Compression
Compression is enabled by default for the O&O DiskImage format. Standard Lempel-Ziv is a good general-purpose choice. Maximum Lempel-Ziv and BZIP options can save more space but take longer. ZIP deflate is available for file backups, not disk images. VHD/VHDX do not use these compression settings.
Encryption
Set the password before creating the first backup. Keep it in a password manager or another safe place: encrypted backups cannot be restored without the original password.
Once a plan has saved versions, its encryption, password, image format, backup technology, and exclusions are locked, including while those versions are offline. Create a new plan to use different settings. History, compression, validation, reports, and naming templates remain editable.
If a stored password is no longer available to the application, re-enter the original password on the plan page. This restores access; it does not change the password. Backups are blocked until the password is available.
Validation
Enable the option to check the backup afterwards to verify its integrity and readability. Validation reads the backup without restoring data or changing the source. It adds time to the operation and does not replace a recovery test.
You can also check an existing backup under Restore > Utilities. Recovery partitions are included in validation; the former option to skip them has been removed.