ftp transfer breaks php

[nikohak]

I have a simple email subscribtion php-script that collects users email addresses to a text file. I have similar text file on my computer and I would like to combine them manually.

 

For some reason if I download the txt-file from the server add the emails and upload it back, the system stops working (adding new emails when someone uses the form). This even happens if I download the txt-file and then upload it back without even opening it locally?

 

I've checked permissions for that file and they remain the same. Can it be some sort of uploading/encoding issue?

I've tried transfering as text & binary but it doesn't help. When I open the downloaded file in notepad it says it is using ANSI encoding.