Get file from GridFS by it's Id

Hi,
I’m trying to get a file by it’s Id and it simply does not work.
Setting the filter in different ways:

This just finds nothing and returns null.
var filter = Builders.Filter.Eq("_id", objectId);
This just throws this exception: “mongodb Unable to determine the serialization information for x => x.Id.”
var filter = Builders.Filter.Eq(x=>x.Id, objectId);

So, what’s the right way to do this?
I’m on .net core 3.1 and GridFS Driver 2.13.2.

Regards
Thomas

Hi @Thomas_Leclaire and welcome in the MongoDB Community :muscle: !

I think you are missing something like new ObjectId(objectID).

Because "621cb5142db31bf727d6028d" != ObjectId("621cb5142db31bf727d6028d")

Cheers,
Maxime.