Try to empty char array.

Projects Programming
2

Hi,
SdBestand is a global variable that is continously updated by appending new text at every cycle of the loop:

   while (SD.exists(SdBestand)==true) {
      Nummer++;
    //has to empty the char SdBestand!!!
      itoa(Nummer,Cijfer,4);
      strcat (SdBestand, Logging);
      strcat (SdBestand, Cijfer);
      strcat (SdBestand, txt);
     }

simply change the first "strcat" with a "strcpy". This function copies a string (the second argument) in another (the first argument) overwriting the initial content. Another solution is to reset the string with a terminator character:

SdBestand[0] = '\0';
strcat(...);
strcat(...);