There is also a train connection via the UBahn (underground) if you don't have too much luggage. The UBahn is close to everywhere in the city and connection to the airport really easy.
Sorry for the broken link, but it's the only way to post it here on TA...
The airport shuttle stops a few hundred metres from Post on Schwedenplatz.
You can read up on the shuttle route here, including where you'll find it at the arrival hall here viennaairport (.) com/ en/ passengers/ arrival__parking/ bus_connections
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