Question: I'm trying to remove dollar signs and commas from my form input (for example, $1,000.00 => 1000.00)

I have the following following line in my before\_validation method in my model:

```
self.parents_mortgage = self.parents_mortgage.to_s.gsub!('$,','').to_i

```

This is causing any number to be put through to zero out. Is there something wrong with my syntax?

Answer: 
Is it possible there's a little bitty bit of whitespace outside of the PHP tags in blabla.php line 581? I bet there is.

See, if you have **anything** outside of PHP tags, that is sent to the browser. And once something has been sent to the browser, you can't send headers (like the sessionID cookies!) anymore.

The problem is likely not XAMPP, but your PHP code as you put it on the flash drive.
The difference you're seeing between environments is most almost certainly a difference in the configuration.

One of two things is happening on the server that isn't emiting Warnings:

1) [Output buffering](http://us3.php.net/manual/en/outcontrol.configuration.php#ini.output-buffering) is on by default

2) [error\_reporting](http://us3.php.net/manual/en/errorfunc.configuration.php#ini.error-reporting) and/or [display\_errors](http://us3.php.net/manual/en/errorfunc.configuration.php#ini.display-errors) is set so you're just not seeing the warnings. But if this were the case, your headers still wouldn't get set, so it's probably #1

You can check these settings by looking at the output from `phpinfo()`

Output buffering, when enabled, buffers any output (regular content not inside tags, anything you echo or print(), etc) on the server and then sends it to the client in one shot. 

I'd poke around in your portable version, find php.ini, and try turning output buffering on. Alternatively, you can turn output buffering on at runtime by sticking `ob_start()` near the top of your script.