Thank you guys

Regarding the error, the simply message in the Output Log window is: ""expert advisor is not exported. Cannot create the expert file."

Fast and clear!

Thanks Popov, but i got the same problem. It doesn't export the EA.

I also tried to copy the mqh in every folder of indicator, but nothing

I think you might be using your own modified indi with a different name (Time Grid Prova vs Time Grid), but it doesn't work because the naming is different between .cs and .mqh. Please add the error message itself also, then we don't have to guess what error is about.

Thanks Popov, but i got the same problem. It doesn't export the EA.

I also tried to copy the mqh in every folder of indicator, but nothing

The first one is used in FSB and the second one in the exported Expert Advisors.
If you want modifications, you have to modify both files in order to achieve the same results in MetaTrader.

What's the problem?

The "error" popup still remains....

Clean the Library folder. The old dll causes the conflict.

This message shows you that the indicator is already loaded from the original file TimeGrid.cs

If you want to use your version together with the original, you have to rename the class and the constructor, and the indicator name text.

    public class TimeGridProva : Indicator
    {
        public TimeGridProva()
        {
            IndicatorName     = "Time Grid Prova";
            PossibleSlots     = SlotTypes.OpenFilter;

The "error" popup still remains.... but now it works perfectly!
Thanks again

If you want to use your version together with the original, you have to rename the class and the constructor, and the indicator name text.

    public class TimeGridProva : Indicator
    {
        public TimeGridProva()
        {
            IndicatorName     = "Time Grid Prova";
            PossibleSlots     = SlotTypes.OpenFilter;

I'm sure i did something wrong with note++, since it's the first time for me...

These cases are labels that separate the days of week. If you have several labels, all execute the same code.

case DayOfWeek.Monday    :

You can put conditions between the label if you want. Every condition finishes with "break;". If you miss the "break;" the program will continue with the next label.

For example the following code allows entries from 8:00 to 20:00 from Monday to Thursday and from 8:00 to 12:00 for Friday.

    switch(Time[bar].DayOfWeek)
    {
        case DayOfWeek.Monday    :
        case DayOfWeek.Tuesday   :
        case DayOfWeek.Wednesday :
        case DayOfWeek.Thursday  :
            values[bar] = (hour >= 8  && hour < 20) ? 1 : 0;
            break;
        case DayOfWeek.Friday :
            values[bar] = (hour >= 8  && hour < 12) ? 1 : 0;
            break;
        case DayOfWeek.Saturday :
        case DayOfWeek.Sunday   :
            values[bar] = 0;
            break;
    }