I'm glad to hear you found the answer for the issue, if you have any other issue about SharePoint, you are welcome to raise a ticket in this forum.
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[Why cant I find the Osearch16 vss writer on my sharepoint server SE installation?]
Issue Symptom:
OP is using Dell Avamar to back up systems. When trying to backup SharePoint on-premise server Subscription edition, getting errors referring to Osearch16 VSS writer. OP can't find this writer on our system, neither on the frontend (FE/Cache) or application-server (App/Search).
Search is activated and working. Only writer OP find on the server (vssadmin list writers) is "SharePoint services writer". Dell says OP must have the "Osearch16 VSS Writer".
How can OP enable this writer?
Current status:
There was a mismatch between the service accounts used on the windows service "SharePoint search host controller" vs the account registered in SharePoint central admin for the search host controller service. When these two where aligned, after a while the writer appeared in the list of writers again.
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