Symptoms

1. You have one of the following products:
   • Acronis True Image 2017 New Generation
   • Acronis True Image 2018/2019/2020
   • Acronis Backup 12.5.
2. You want to delete a backup file using Windows Explorer.
3. Deletion fails with a "Folder access denied" error:
   

Cause

Acronis Self-protection is turned on. Self-protection is a setting of Acronis Active Protection that protects Acronis own processes, backups, and archives from ransomware, unauthorized changes, or deletion.

Solution

We recommend deleting backups in product interface. See product documentation for instructions:

• Acronis True Image 2019 and 2020: see article Acronis True Image 2019 and 2020: How to delete old backups 
• Acronis True Image 2018: Deleting backups and backup versions
• Acronis True Image 2017: Deleting backups and backup versions
• Acronis Backup 12.5: Deleting backups

If you absolutely need to delete backups manually in Windows Explorer, do the following.

In Acronis True Image 2019 and 2020:

When you attempt to delete a backup via Windows Explorer, a pop-up window will appear to warn you about a program modifying your files.

Click Allow. Acronis True Image will remember this selection and will not block backup deletion via Windows Explorer in future. 

If such pop-up window does not appear, follow instructions for version 2017 below.

In Acronis True Image 2018:

When you attempt to delete a backup via Windows Explorer, a pop-up window will appear to warn you about a program modifying your files.

Click Allow for one hour.

If such pop-up window does not appear, follow instructions for version 2017 below.

In Acronis True Image 2017 New Generation:

1. Open Acronis True Image.
2. On the sidebar, click Settings.
3. Find Acronis Active Protection section.
4. Clear the check mark from Protect all Acronis True Image files from ransomware.
5. Delete files.
6. Mark Protect all Acronis True Image files from ransomware again to enable Self-Protection.

In Acronis Backup:

1. Open Acronis web console.
2. In Devices, find the affected machine.
3. Click Active Protection.
4. Click Edit.
5. Disable the Self-protection switch.
6. Save changes.
7. Delete files.
8. Enable Self-protection.