I have enough problems when I try to put HTML or XML snippets in my code. I was trying all kind of stuff. Now I’m using a plugin named Code Autoescape. This All you have to do is to download it as a textfile from this link, rename it as php, upload it in wp-content/plugins of your wordpress installation and activate it from WordPress administration page.

When the plugin is enabled you can white the code like this:

<code><HTML> </HTML></code>

If you want to insert multi line codes you have to put it in <pre> tags:

<pre> <code>

<lineone> </lineone>

<linetwo> </linetwo>

</pre></code>

When I edit the articles containing code I always take care to deactivate the default wysiwyg wordpress plugin, because it changes the article when it loads it in an undesired manner. I deactivated it from Users > Your Profile, unchecking this:

Use the visual editor when writing

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