Using HappyFox's New Ticket Auto Responder Notification, you can create a Template and use as your Helpdesk's Holiday/Vacation Auto-mailer. 

Applicable Plans: ✔️ Mighty ✔️ Fantastic ✔️ Enterprise ✔️ Enterprise Plus

Set-up procedure:

• Login to your HappyFox account as an agent.
• Go to Manage >> Notifications >> New Ticket Auto-responder >> + (Add new Template).

• Enter the name and subject of the email. Once you've done all the necessary editing, and have added your required content in the template, click Create to add the new template.
• Select the notification template for each of your categories under the Manage Notification section.

Add an image to your auto-mailer:

• Upload the image to a publicly accessible location - TinyPic, Dropbox, Google Drive, etc.
• To add the image in the email content, click Source to bring up the HTML editor tool.
• Add the direct link to the image inside a <img src=""/> tag as below: <img src="your-image-URL-source"/>. Replace your-image-URL-source with the direct link to your image. 
• The image can be resized by dragging on the corners.