Joomla custom template error

Question

I'm trying to create a custom template at Joomla but I get the following error:

Error Unable to write entry Unable to find install package

my template Zip ha the following folders:

christinas
-css
--template.css
-js
--template.js
-images
index.php
templateDetails.xml

my templateDetails.xml is the following :

<?xml version="1.0" encoding="utf-8"?>
<extension version="3.3" type="template" client="site" method="upgrade">
    <name>christinas</name>
    <creationDate>Sep 2016</creationDate>
    <author>me</author>

    <copyright>Copyright (C) 2010 - 2016. All rights reserved.</copyright>

    <version>1.1</version>
    <description>My Template</description>

    <positions>
        <position>title</position>
        <position>top1</position>
        <position>top2</position>
        <position>top3</position>
        <position>logo</position>
        <position>menu</position>
        <position>search</position>
        <position>slide</position>

    </positions>

    <files>
        <file>index.php</file>
        <file>templateDetails.xml</file>
        <folder>css/</folder>
        <folder>images/</folder>
        <folder>js/</folder>

    </files>

</extension>

Which is the proper fileset for a joomla template?

Answer 1

Shouldnt it be

<filename>index.php</filename>