Zen Cart is generally a very reliable shopping cart program. It can be quite testy at times, though, and there are some surprisingly simple issues that can end up breaking your entire website if they are not fixed quickly. In this zen cart tutorial, we will take a look at one of these scenarios. The problem demonstrated here is pretty straightforward. Let’s say that you have encountered some pages blank pages across your website. These pages are completely white and empty, except for these characters: ‘ï»¿’.
This is caused by characters(most likely from an unsupported char set), which have ‘invaded’ one of more of the files in your zen cart store. There are a number of ways in which these characters can be dumped into your files, but the most common is through file editing programs. Whenever you edit zen cart files, you should always do so in a plain text editor. Anything else is likely to insert characters like these, which can break your site horribly. Even worse, most of them are invisible, so you won’t know they are there until it’s too late!
To fix this problem, you will need a bit of help from the zen cart debugger log files. Look through them until you find an error message that looks something like this:
PHP Warning: Cannot modify header information - headers already sent by (output started at /home/your_name/public_html/includes/languages/english/header.php:1) in 'xxxx' on line 'xxx'.
This error message is very important, as it tells you exactly what line, in what file the unsupported characters have been dumped. Once you know which file has been affected, all you need to do is edit the file(In a plain text editor!), and save it in “UTF-8 without BOM” encoding/format.