As I'm sure some of you have also had these problems MT4 requires a huge hard drive to store all the testing files for many currencies, I recently found using /portable in the shortcut puts all of the data in the mt4 folder which allows me to move it to any HHD that I choose, GREAT!
Only problem is that I now get NA in my testing reports, does anyone know how to fix this?
This value is practically of no importance. Either you use self created tick data or you use the option of the terminal (tick, control points, open) then you know yourself about the quality of your backtest.
E.g. Tickstory writes the 99%.