Normally You will need to 1st correct the situation that brought about this condition after which reconnect manually utilizing plugin context menu explained underneath. Alternativelly you may just restart AmiBroker. Assuming you've procured historic data for US delisted, and already have the data installed, observe these steps: Unfortunatelly this https://dataforamibroker20863.blogolenta.com/24887276/the-ultimate-guide-to-amibroker-data