LDAP-User not found using WebDav-API


I am using the WebDav-API for managing files/folders (creating folders, uploading downloading files, Removing files &folders, …) in a hosted Nextcloud (15) environment. (Basic APIs )
Users have been created manually and content can be accessed via “http://server/remote.php/dav/files/username/…”. I ve used the “Full name” for username and authentication.

This “module” has now been installed for a Nextcloud 13.0.2 where users will be authenticvated via LDAP. Log in via browser is working well for fullname, shortname and Mailadress. When using the API Nextcloud throws an error XML:

<?xml version="1.0" encoding="utf-8"?>

<d:error xmlns:d=“DAV:” xmlns:s=“http://sabredav.org/ns”>
<s:message>Principal with name username not found</s:message>

I have no idea is there are configuration have to be made for using LDAP-User via API, or which kind of name should be used for authentication and/or for request-url. Maybe someone has some experience with this or a similar case?
Is there any possibility to find out which “usernameversion” has to be used?
Does anyone knows a way of showing a list of names which the API needs?
I am searching a while for solution or possible hints to solve the problem without success.

I would be happy about any suggestion or hint to that case.

best regards

P.S. Another question (Yes/No): Is a 2-way-authentication possible to use together with WebDav-API ?

Hello, Michael.

I have same issue with Nextcloud 19. Did you find some solution or workaround?

Best regards

Well it’s a long time unanswered but it looks like the user GUID works for LDAP.