B
char Fenstername[50];
sprintf(Fenstername,"%s - Nachrichtensitzung","derName");
HWND ICQ = FindWindow (NULL, Fenstername); //Fenster finden
HWND ICQEDIT = FindWindowEx(ICQ,NULL,"RichEdit20A",NULL);
SendMessage(ICQEDIT ,WM_SETTEXT,0,(LPARAM)dentext);