Environment

Data Protector version: 11.02
Operating System on Cell Manager: Windows Server 2022
Operating System on Disk Agent: Windows 10

Situation

After reboot first backup works, however every backup fails afterwards

[Warning] From: VBDA@DiskAgent "DiskAgent [\\?\Volume{fc7b827-e157-4b2e-b3f3-c03ef3861663}\]" Time: 11/29/2023 12:38:38 PM
    Volume Shadow Copy functionality could not be initialized.

[Warning] From: VBDA@DiskAgent "DiskAgent [\\?\Volume{fc7b827-e157-4b2e-b3f3-c03ef3861663}\]" Time: 11/29/2023 12:38:38 PM
    Fallback to legacy filesystem backup.

[Critical] From: VBDA@DiskAgent "DiskAgent [/CONFIGURATION]" Time: 11/29/2023 12:38:38 PM
    Volume Shadow Copy functionality could not be initialized.

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