Updating to Ladybug 0.0.69 and Honeybee 0.0.66 [Legacy Plugins] from food4Rhino might solve this. Other users faced this issue. Please search the forum for what worked for them.
Updating is always a good idea and it’s possible this may be the issue. If you still get the error after updating, make sure that you are connected to the internet the first tie that you run the GenCumultaiveSkyMtx component.