By Ivy / Last update November 11, 2021

Case: Windows Server Backup not overwriting old backups

I set a schedule full backup to a volume in Windows server 2008. It running smoothly until today, now my full backup failed due to the disk full and contains 2 old backups. I thought the old backups will be deleted automatically to keep the newest backup after several backups; I don’t have any other options to modify. How can I keep the most recent versions of the backup and overwrite the oldest backup to spare space on my hard disk?

Windows Server Backup (WSB) is the built-in backup utility in Windows Server 2008, 2012, 2016, 2019, 2022, etc. It enables you to backup folders, volumes, system state, entire disk, or even perform bare metal backup and recovery. 

In practice, WSB may fail for various reasons, such as backup disk full. This is confusing to many users because WSB is supposed to auto delete old backups when there is not enough space. So what interrupts this mechanism?

Windows Server Backup Failed Error

How does Windows Server Backup disk management work 

Windows Server Backup creates a virtual hard disk (VHD) file for the source volume when you perform a backup, especially Windows Server Backup to network share incremental, and then create a shadow copy of the destination volume where is the backup image file located. Then the backup time, shadow copy identifier (Shadow Copy ID) and Version identifier will be updated in backup catalog. Then, you could restore to previous versions with these shadow copies.

If the target storage location is full, Windows Server Backup auto delete old backups to spare room for the current backup. More specifically, when WSB detects there is not enough space on the disk to accommodate a new backup, the automatic disk management feature will shrink the storage space allocated for snapshots, deleting one or more old snapshots that occupy the shrunken diff area, along with the corresponding backup version.

But please note:

Windows Server Backup will not shrink the storage space of shadow copies to 1/8 below the target volume size. That’s why your backup failed and Windows Server Backup not deleting old backups.

By the way, there is no such thing about backup limit number of Windows Server Backup copies.

Make Windows Server Backup overwrite old backups now

You have two ways to make Windows Server Backup remove older backups: Change snapshot storage or Delete old backups manually.

Way 1. Change snapshot storage

1. Double click the Computer, right click the volume contains shadow copies (snapshot), choose Properities.

2. In Shadow Copies section, press Settings to change the path.

Shadow Copy Settings

Way 2. Delete old backups manually (not recommended)

You could use wbadmin delete systemstatebackup command to delete the system state backups. If you are planning to delete other kinds of backups, try WBADMIN built-in backup utility.

1. Click Start, and input cmd in search box, run as administrator.

2. First of all, run the following command to track Windows Server backup multiple copies, like Shadow copy ID, creation time, shadow copy volume, etc.:

vssadmin list shadows 

3. Then delete shadow copies starting from the oldest shadow copy, the command to remove shadow copies from Windows Server in cmd is:

vssadmin delete shadows /For=C: /oldest (change the C: with the right volume that contains the shadow copy which you want to delete)

Delete Shadow Copy Oldest

Or you could run vssadmin delete shadows /For=C: /all to delete all shadow copies. Then you might get free space for another backup. 

However, Windows Server Backup might overwrite old backups (It would not guarantee to get the free space). And sometimes you may find Windows Server Backup keep only one copy.  Thus, it's wise to get easier way to manage multiple backup versions effortlessly, and a professional third party backup software would be suitable for you.

Best solution to backup server and auto delete old backups

The professional backup and recovery software – AOMEI Backupper Server supports backing up system, individual partition, files & folders or entire disk to local drive, external hard drive, network share, clouds, etc. It allows you to create full backup, incremental backup, differential backup, schedule backup with simple clicks.

What's more, it contains powerful backup cleanup feature to delete old backup images automatically with customizable scheme. You could download the free trial and follow the tutorial below to have a try:

Download Free Trial Windows PCs & Servers
Secure Download

1. Open AOMEI Backupper Server, choose Backup, and then click Disk Backup.

Backup Disk

2. Input a proper Task Name, choose the system hard disk to backup by clicking Add Disk.

Add Disk

3. Choose a destination disk to save the backup copy then.

4. Click Backup Scheme and then toggle on Enable Automatic Backup Cleanup, specify retention policy by quantity, by time, or by daily/weekly/monthly.


★ Tip: You can also choose backup method here as full backup, incremental backup or diffential backup.

5. Press Start Backup for Windows Server backup to save backups on limited storage space on disk.

Start Backup Scheme

★ Tips:
Options (optional): this powerful program allows you to comment, compress, split, encrypt the backup image, backup only the used sectors, and more.
This program applied to all Windows Server and PC editions (32-bit and 64-bit), like Windows Server 2003, 2008, 2012, 2016, 2019, 2022 (including R2), SBS 2003, 2008, 2011 and Windows 11, 10, 8.1, 8, 7, Vista, XP.

Besides, you could set Backup Schedule to make the backup running automatically.

  • Daily/Weekly/Monthly: To avoid forgetting to backup, you could set the backup running daily, weekly, monthly to automatically run on a regular basis.

  • Event Triggers: You could trigger the backup task via the following four events: User logon, User logoff, System startup, System shutdown, not affecting your working time.

  • USB plug in: AOMEI Backupper will immediately back up the data on the USB or backup local data to USB device as long as detecting the USB device of the task is plugged in.

Schedule Settings General


After that, you don’t have to worry about the backup limit number of Windows Server Backup. Meanwhile, like Windows Server Backup overwrite old backups, AOMEI Backupper Server will delete older backups to keep the recent backup versions for you after setting up. 

You could go Tools -> Explore Image to manage image files in File Explorer. In the future, you might need to restore the backup file to repair hard disk failure, the software has the ability to restore to identify location or restore to dissimilar hardware computer, etc. 

 And if you want to protect unlimited PCs and servers within your company, you may choose AOMEI Backupper Technician Plus. It offers unlimited billable technical services to clients. It also enables you to copy installation directory for portable version creation.