[DOS] the "cd" command only points to C:\

Hello,

I have a problem that I've never encountered before and for good reason...

On my server (Windows Server 2008 R2), the simple command to change to a folder only works for drive C:. Let me explain:
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C:\users\administrator>cd C:\MyFolder
C:\MyFolder>
--
-> it works fine there. However, if I point to another drive, here's the result:
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C:\users\administrator>cd D:\MyFolder
C:\users\administrator>
--
For your information, the administrator account has full control over drive D:

I don't understand
Thank you for your help