i have this code:

$result = mysql_query('select * from login');
$count = mysql_num_fields($result);

for ($i = 0; $i < $count; $i++){
    $header .= mysql_field_name($result, $i)."\t";

while($row = mysql_fetch_row($result)){
  $line = '';
  foreach($row as $value){
    if(!isset($value) || $value == ""){
      $value = "\t";
# important to escape any quotes to preserve them in the data.
      $value = str_replace('"', '""', $value);
# needed to encapsulate data in quotes because some data might be multi line.
# the good news is that numbers remain numbers in Excel even though quoted.
      $value = '"' . $value . '"' . "\t";
    $line .= $value;
  $data .= trim($line)."\n";
# this line is needed because returns embedded in the data have "\r"
# and this looks like a "box character" in Excel
  $data = str_replace("\r", "", $data);

# Nice to let someone know that the search came up empty.
# Otherwise only the column name headers will be output to Excel.
if ($data == "") {
  $data = "\nno matching records found\n";

# This line will stream the file to the user rather than spray it across the screen
header("Content-type: application/octet-stream");

# replace excelfile.xls with whatever you want the filename to default to
header("Content-Disposition: attachment; filename=excelfile.xls");
header("Pragma: no-cache");
header("Expires: 0");

echo $header."\n".$data;

the problem is that it is displaying everything in the first field

I have tested you code and found that it works.
the only thing I did different was place this code at the top of the script: error_reporting(E_ALL ^ E_NOTICE); once I did that it worked fine. It may not be the best solution, but it did work after I placed that within the code.