(0x81000036) Close Windows Backup and try again.
Error 0x81000036, Windows could not find backup devices
If you are receiving Windows Backup Error 0x81000036, the following solutions may help you:
1] Disable Windows Sandbox
According to the feedback of many affected users, the error 0x81000036 got fixed on their system when they disabled Windows Sandbox. You can also give this method a try and see if it helps.
The steps to disable the Windows Sandbox in Windows 10 are listed below: Restart your computer. If this method does not fix the error on your computer, try the next solution.
2] Disable Hyper-V
Hyper-V is another culprit of this issue. If you have enabled the Hyper-V on your system, consider disabling it and see whether it solves the issue or not.
The steps to disable Hyper-V on Windows 10 are as follows:
3] Turn Off the USB ports
If none of the above methods helped you, try to disable the USB ports temporarily and then create a system image backup. Many users have found this method helpful. Maybe it will work for you too. Hope this helps. Related posts:
Create a System Image backup failed with error 0x80780172.System Image Backup fails with error codes 0x807800C5 and 0x80070020.