MT3 - default constructor error message

When I try to attach a strategy to a chart the following message appears
unable to create instance of class
NinjaTrader.strategy.MicrotrendsMT3 most likely there is no default
constructor defined or the default constructor does not work correctly

It sounds as if you have not got the latest verson 7.0.0.38 installed?

if that is not the issue then deleting the strategy tempalte will be the only way to resolve it and trying again.