Lindsay Lohan hit the L.A. County Morgue in style this morning … rolling up in an $80,000 Porsche Panamera … before being turned away at the door.

Lindsay was spotted at a back entrance … talking with a morgue staffer who appeared to be informing the actress that she needed to go to a different entrance … redirecting her to the front of the building.

LiLo was 40 minutes late … and the Coroner’s Office sent her ass home without credit.

Lohan claims she’ll try again tomorrow.

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