Error while extending schema with schema wizard: "A referral was returned from the server." (4260645)

LDIFDE Results:

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Add error on line 16: Referral
The server side error is "A referral was returned from the server."
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An error has occurred in the program

Referral returned means the root DC name is incorrect.

 Schema wizard connects to LDAP://rootDSE and reads defaultNamingContext from there, which in turn determines the domain Distinguished Name (DN) used by ldifde. rootDSE is determined by the user logged in, instead of the domain that the machine is joined to.

 As an example:
 For a user member of child.domain.com, who is logged into a machine in domain.com, and is trying to extend schema in domain.com, the schema wizard will read the defaultNamingContext of "DC=child,DC=domain,DC=com" (as determined by the user logged-in). This may result in an operation like this:
 ldifde -s dc01.domain.com -i -f "C:\schema\win32\ldif\VAS_SC~8.LDI" -c "DC=X" "DC=child,DC=domain,DC=com"

 The above will fail, as "dc01.domain.com" is not the DC for "child.domain.com".

Log in as a member of the specific domain where schema is being extended.

This will make the schema wizard use the correct defaultNamingContext/domain DN and the DC, while carrying out the schema extension.