Why do I get "Supplier Disabled" in my Altium BOM
Even though it was taking me to the suppliers website, the suppliers name was not quite correct (or at least how Altium expects it).

Specifically, the ones that had a problem had the supplier as DigiKey and Altium was expecting Digi-Key.

To change all of these wrong supplier names at once, I used Parameter Manager in the Tools menu.

Aditionally, you may have to enable the supplier in the DXP Preferences - Data Management - Suppliers page: