I am ineligible to enter the Schengen area right now since I've exhausted my 90/180 days. However, there is an month long internship offer in Europe that I am keen to take up. Is there any possibility of getting a D class visa for a 1 month visit? (I assume the host institution will be willing to help me get one. They do this regularly for other students who stay longer).
Correcting myself. The previous answer was not correct.
Here's the Italian official website:
Long sojourn or "national" Visas (NV), which are only valid for visits that are longer than 90 days (type D),
That's quite clear.