int init()
  {
//+------------------------------------------------------------------+
   string ls_0 = "2018.04.18";
   int str2time = StrToTime(ls_0);
   if (TimeCurrent() >= str2time)
   {
      Alert("Your License Has Expired! Please Renew The License.");
      return (0);
   }
  /*
   if (AccountNumber() != 72520)
   {
      Alert("Invalid Account Number! Only Licensed For Account Number 72520.");
      return(0);
   }*/
//+------------------------------------------------------------------+

 return(0);
 }

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I am using the above script in several of my EA. It has become difficult to edit AccountNumber  and change the code and Expiry Date and recompile the EX4 file.
So I need to create an External Licensing System to validate the AccountNumber and Expiry Date, and the logic is very simple.

The code inside the MQ4 file will have the following values assigned to the numbers 0 to 9:
PH==0 || ST==1 || GW==2 || RM==3 || CV==4 || UA==5 || BD==6 || LX==7 || ZQ==8 || YK==9

I will have 2 text files with renamed extensions to .dll and .bin
The .dll file name will be AccountNumber.dll and .bin file name will be ExpiryDate.bin

For example:
Account Number: 72520.dll will be named as LXGWUAGWPH.dll
Expiry Date: 2018.04.18.bin will be named as GWPHSTZQ_PHCV_STZQ.bin

The .dll and .bin files will be placed inside the folder "Operations" under the following location "Terminal_folder\Experts\Operations\"

The EA has to read the .dll and .bin file name in the "Operations" folder and preform the above code function and verify if the AccountNumber and Expiry Date are valid.

The following articles has information on how to read file names from inside a folder location.
https://www.mql5.com/en/articles/1543 (See Sample Code in this URL : CheckFindFile.mq4)
https://forum.mql4.com/6893
https://www.mql5.com/en/forum/94338

If the .dll or .bin files are missing inside the "Operations" folder
Alert("Missing algorithmic operations DLL and BIN files.");

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