So, your button-code should be:
<?xml version="1.0"?>
<button display="both" icon_size="large">
<label>&Refresh All</label>
<tip>Refresh the contents of both file displays and the Folder Tree</tip>
<icon1>#refresh</icon1>
<function type="normal">
<instruction>Go REFRESH=all</instruction>
</function>
</button>
Look here if you don't know how to create a new button: [url]How to use buttons and scripts from this forum]