Kantakouzenos tries to regain lands the Empire has lost while Dušan launches the Bosnian campaign (absent the Serbian troops in Macedonia and Thessaly).

In support, the Constantinopolitan patriarch Kallistos in 1350 excommunicates Dušan in order to discourage the Greek population in Dušan's Greek provinces from supporting the Serbian administration and thereby assist the Kantakouzenos campaign.

The excommunication does not stop Dušan's relations with Mount Athos, which still address him as Emperor, though rather as Emperor of Serbs than Emperor of Serbs and Greeks.

Kantakouzenos raises a small army and takes the Chalcidic peninsula, then Veria and Voden.

Veria is the richest town in the Botia region.

Dušan had earlier replaced many Greeks with Serbs, including a Serb garrison.

However, the remaining locals are able in 1350 to open the gates for Kantakouzenos.