I was running Covered Call Option tutorial from 

https://github.com/QuantConnect/Tutorials/tree/master/07%20Applied%20Options%5B%5D/01%20Covered%20Call

I changed the StartDate and EndDate as:

self.SetStartDate(2017, 1, 1)
self.SetEndDate(2017, 7, 1)

After running the backtest I am seeing the following errors in the console. It appears that data is not found, any thoughts ?.

216 | 02:45:34: 
Backtest Handled Error: IBM   170127C00167500: The security does not have an accurate price as it has not yet received a bar of data. Before placing a trade (or using SetHoldings) warm up your algorithm with SetWarmup, or use slice.Contains(symbol) to confirm the Slice object has price before using the data. Data does not necessarily all arrive at the same time so your algorithm should confirm the data is ready before using it. In live trading this can mean you do not have an active subscription to the asset class you're trying to trade. If using custom data make sure you've set the 'Value' property.
217 | 02:45:37: 
Backtest Handled Error: IBM   170224C00177500: The security does not have an accurate price as it has not yet received a bar of data. Before placing a trade (or using SetHoldings) warm up your algorithm with SetWarmup, or use slice.Contains(symbol) to confirm the Slice object has price before using the data. Data does not necessarily all arrive at the same time so your algorithm should confirm the data is ready before using it. In live trading this can mean you do not have an active subscription to the asset class you're trying to trade. If using custom data make sure you've set the 'Value' property.
218 | 02:45:40: 
Backtest Handled Error: IBM   170324C00180000: The security does not have an accurate price as it has not yet received a bar of data. Before placing a trade (or using SetHoldings) warm up your algorithm with SetWarmup, or use slice.Contains(symbol) to confirm the Slice object has price before using the data. Data does not necessarily all arrive at the same time so your algorithm should confirm the data is ready before using it. In live trading this can mean you do not have an active subscription to the asset class you're trying to trade. If using custom data make sure you've set the 'Value' property.
219 | 02:45:44: 
Backtest Handled Error: The security with symbol 'IBM   170324C00180000' is marked as non-tradable.

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