Getting header errors

[fishown]

Hello every one and good morning,
While im running the site files on my computer (wamp2 server),
the site run very well, as soon as i tried to upload it i keep get wierd header errors

its says:
"Warning: Cannot modify header information - headers already sent by (output started at /home/fishown/domains/art-guide.xdf.co.il/public_html/login.php:1) in /home/fishown/domains/art-guide.xdf.co.il/public_html/login.php on line 209"
i wonderd how come that appear only on the dedicated server?

The dedicated server php software version is "PHP Version 5.2.4".

And on my computer the version i dont know.

As well i get some session error,
its says:
"
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/fishown/domains/art-guide.xdf.co.il/public_html/login.php:1) in /home/fishown/domains/art-guide.xdf.co.il/public_html/login.php on line 107"

Thank You veryMuch

[Piranha]

I don't know why it works on your local computer, but I can tell you what the problem is. All headers have to be sent before you output anything to the browser. And the same goes for session_start().

Not even a space is allowed. Or a return. and that goes for the main file and all included files.