Using Canon Speedlite with remote trigger

Hi again,

I just received Nissin Di-866 mark ii from Hong Kong. The item description says it works with Canon cameras as a Wireless Master flash, which I understand that if you put the flash in wireless mode it can be triggered by itself without the additional flash.

I have Canon 5D mark II, but the camera's External Speedlite control menu says, "This menu cannot be displayed. Incompatible flash or flash's power is turned off."

Can you tell me what I need to do in order to trigger this flash from remote? I know that one option is to buy a long sync cord. But I want to figure out the other option. Initially I thought that it should work without any additional parts as a Wireless Master Flash.
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Bat