Windows Server 2019 / Windows Search not working on one share

Hi All,

We have two Windows Server 2019 File Servers, AD-DCs, DFS.

On both servers, Windows Search feature is installed, the service set to automatic and started.

On both servers, I added local drives which host shares to the search index.

The servers are in different sites, connected by VPN.

Clients access the servers only via mapped drive letter to the server-name, never using a DFS name.

On one of both servers, one share's search function is not working. Not when queried from the client, not when queried from the server using a mapped drive.

The search is working on the server when searching on the local drive where the share is hosted.

The share is the only data on that local drive.

The share which is not working on one of the servers is the only share that is replicated using DFS to the other site. As mentioned above, the mapped drive is only mounted using the sites server name, NEVER the DFS name.

I can't figure out why this specific share is not working on one of the servers.

I can't find where to look for errors. Nothing to find in the event-log, no useful log files I know of.

How do I best troubleshoot this problem? Is there a way to activate verbose logging for the indexing service?

Thanks a lot for your help!

Thomas