Microsoft Outlook and Thunderbird are among the most popular email client softwares used across the world. Both of them come with built-in features that allow users to set automatic messages during your absence from work.
Enable Automatic Replies under Outlook
Click the File menu > Info
Click on Automatic Replies (Out of Office).
Check Send Automatic Replies
From there you can define a time range for the automatic replies by checking the "Only send during this time range" options
In the other case, automatic replies will be send until the "Do not send automatic replies" option is checked.
You can also define, the type of users who will recieve these messages:
Inside My Organization
Outside My Organization
Save your settings.
Enable Automatic Replies under Mozilla ThunderBird
The procedure is slightly more complicated with Mozilla Thunderbird.
You must first create a new message, then save as a template, such as "Summer Holidays"
Then, open the Tools > Message Filters > New and then complete the following fields:
Give a name to your filter (e.g "Summer Holidays")
Apply Filter > When receiving mail
Select the "validate all the following conditions"
Add condition "From" > "Does not contain" > "noreply" to avoid sending an automatic reply to automated messages.
Click on the + button to add the second condition: "From" "Contains no" "no-reply".
Perform these actions > Reply with Template
Select the "Summer Holidays" template, create earlier.