[SOLVED]Fatal error: Call to a member function setSaveParametersInSession() on a non-object

If you get "Fatal error: Call to a member function setSaveParametersInSession() on a non-object"


check if your config.xml is properly formatted and class names are between XML tags without new lines

Wrong:

<blocks>
    <some_widgets>
        <rewrite>
            <adminhtml_some_info>ClassName
            </adminhtml_some_info>

    </some_widgets>
</blocks>

OK:

<blocks>
    <some_widgets>
        <rewrite>
            <adminhtml_some_info>ClassName</adminhtml_some_info>
    </some_widgets>
</blocks>