A new update was just released today, fixing that error. All you have to do is to use the "Check for Updates" feature located under the Auto Reply Manager toolbar, then download/install the update and restart Outlook. It should fix it.
If it doesn't fix it, please email us at
mailto:support@emailaddressmanager.com with the entire files content of the HTMLTemplates folder (and options.xml file) located under the installation folder of Auto Reply Manager (by default, the path should be C:/Program Files/DS Development/Auto Reply Manager).
Regards,
Bogdan