PS C:\Users\admin> diskpart

Microsoft DiskPart version 10.0.22000.1

Copyright (C) Microsoft Corporation.
On computer: WIN11

DISKPART>

DISKPART> list volume

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 0     D   VBox_GAs_7.  CDFS   CD-ROM        52 MB  Healthy
  Volume 1     C                NTFS   Partition     79 GB  Healthy    Boot
  Volume 2                      FAT32  Partition    100 MB  Healthy    System
  Volume 3                      NTFS   Partition    611 MB  Healthy    Hidden
  Volume 4         MyDATA       NTFS   Partition    953 GB  Healthy

DISKPART> select volume 4

Volume 4 is the selected volume.

DISKPART> attributes volume
Read-only              : No
Hidden                 : No
No Default Drive Letter: Yes
Shadow Copy            : No

DISKPART> attributes volume clear nodefaultdriveletter

Volume attributes cleared successfully.

DISKPART> attributes volume
Read-only              : No
Hidden                 : No
No Default Drive Letter: No
Shadow Copy            : No

DISKPART> exit