strategytester not working on paid experts

 

hi everyone

i read this article: https://www.mql5.com/en/articles/586

i can test free experts on strategytester but when i want to test market experts on strategytester ,it doesnt work and takes no position and result is empty. what is the problem?




How to Test a Trading Robot Before Buying
How to Test a Trading Robot Before Buying
  • 2012.11.09
  • MetaQuotes Software Corp.
  • www.mql5.com
Buying a trading robot on MQL5 Market has a distinct benefit over all other similar options - an automated system offered can be thoroughly tested directly in the MetaTrader 5 terminal. Before buying, an Expert Advisor can and should be carefully run in all unfavorable modes in the built-in Strategy Tester to get a complete grasp of the system.