Program: 81125
Project: 81125
Buggy source:
/** 
 * Sets the current email address (username) for the program to use. Note that if the username does not contain an ending (&#64;site.net) or is null, &#64;yahoo.com is automatically appended to the end of the username. If the site ending does not end in &#64;yahoo.com or &#64;gmail.com, the program parses the SMTP server addess after the address ending and two colons.<br> Example: User&#64;site.com::site.smtp.server<br> This also (optionall) parses the site's SMTP port after the SMTP server address and a colon.<br> Example: User&#64;site.com::site.smtp.server:123
 * @param user The username to set
 */
public static void setUsername(String user){
  if (user == null) {
    username="String_Node_Str";
    props.put("String_Node_Str",getUsername());
    return;
  }
  if (!user.contains("String_Node_Str")) {
    user+="String_Node_Str";
    setHost("String_Node_Str");
  }
 else   if (user.toLowerCase().contains("String_Node_Str")) {
    setHost("String_Node_Str");
  }
 else   if (user.toLowerCase().contains("String_Node_Str")) {
    setHost("String_Node_Str");
  }
 else {
    String extraInfo=null;
    try {
      extraInfo=user.toLowerCase().substring(user.indexOf("String_Node_Str") + 2);
    }
 catch (    Exception e) {
    }
    if (extraInfo == null) {
      ErrorHandler.showErrorWindow("String_Node_Str","String_Node_Str",null);
      username="String_Node_Str";
      return;
    }
    setHost(extraInfo.substring(0,extraInfo.indexOf("String_Node_Str")));
    if (extraInfo.contains("String_Node_Str")) {
      setPort(extraInfo.substring(extraInfo.indexOf("String_Node_Str") + 1));
    }
    user=user.substring(0,user.indexOf("String_Node_Str"));
  }
  System.out.println("String_Node_Str" + user);
  username=user;
  props.put("String_Node_Str",getUsername());
}

Fixed version (ground truth):
/** 
 * Sets the current email address (username) for the program to use. Note that if the username does not contain an ending (&#64;site.net) or is null, &#64;yahoo.com is automatically appended to the end of the username. If the site ending does not end in &#64;yahoo.com or &#64;gmail.com, the program parses the SMTP server addess after the address ending and two colons.<br> Example: User&#64;site.com::site.smtp.server<br> This also (optionall) parses the site's SMTP port after the SMTP server address and a colon.<br> Example: User&#64;site.com::site.smtp.server:123
 * @param user The username to set
 */
public static void setUsername(String user){
  if (user == null) {
    username="String_Node_Str";
    props.put("String_Node_Str",getUsername());
    return;
  }
  if (user.length() < 3) {
    System.out.println("String_Node_Str");
    username="String_Node_Str";
    props.put("String_Node_Str",getUsername());
    return;
  }
 else   if (!user.contains("String_Node_Str")) {
    user+="String_Node_Str";
    setHost("String_Node_Str");
  }
 else   if (user.toLowerCase().contains("String_Node_Str")) {
    setHost("String_Node_Str");
  }
 else   if (user.toLowerCase().contains("String_Node_Str")) {
    setHost("String_Node_Str");
  }
 else {
    String extraInfo=null;
    try {
      extraInfo=user.toLowerCase().substring(user.indexOf("String_Node_Str") + 2);
    }
 catch (    Exception e) {
    }
    if (extraInfo == null) {
      ErrorHandler.showErrorWindow("String_Node_Str","String_Node_Str",null);
      username="String_Node_Str";
      return;
    }
    setHost(extraInfo.substring(0,extraInfo.indexOf("String_Node_Str")));
    if (extraInfo.contains("String_Node_Str")) {
      setPort(extraInfo.substring(extraInfo.indexOf("String_Node_Str") + 1));
    }
    user=user.substring(0,user.indexOf("String_Node_Str"));
  }
  System.out.println("String_Node_Str" + user);
  username=user;
  props.put("String_Node_Str",getUsername());
}