1) Open the vdcadmintool service tool with the below command:

cd c:\Program Files\VMware\Infrastructure\VMware\CIS\vmdird

2) Type vdcadmintool.exe

3) Press enter and you will see the below menu

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Please select:
0. exit
1. Test LDAP connectivity
2. Force start replication cycle
3. Reset account password
4. Set log level and mask
5. Set vmdir state
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4) Press 3 to enter the Reset account password option
5) When prompted for the Account DN, type:

cn=Administrator,cn=users,dc=vSphere,dc=local

6) Press Enter and a random password will be generated