Mail aliases, forwarding, auto-responders

Once you have a mailbox, you’ll often want more — info@ and contact@ in the same mailbox, an auto-reply for vacation, forwarding to a personal address. Plesk does all of that in the GUI. Here’s how.

Aliases

An alias is a mail address that exists without its own mailbox — incoming mail is delivered to an existing mailbox.

Use case: you have info@deinedomain.de as your main mailbox. You want kontakt@, support@, hello@ to land there too, without separate mailboxes.

Creating an alias

In Plesk: Domain → Mail → click the mail address (mailbox) → Alias tab → +.

Enter the alias name you want, e.g. kontakt. Plesk appends the domain automatically.

Multiple aliases per mailbox are possible.

Alias vs. mailbox

• Alias: no quota, no login, simply delivers to the main mailbox
• Mailbox: its own quota, its own login, its own mail

On a limited plan: aliases are “free” with respect to the mailbox limit.

Replying as an alias

In your mail client you can configure multiple identities. When replying, you pick the sending address:

• A reply to a mail sent to kontakt@deinedomain.de can go out as kontakt@deinedomain.de (the recipient doesn’t see that info@ is behind it)

Setup in the mail client:

• Apple Mail: Settings → Account → add aliases
• Outlook: via manual identity configuration
• Roundcube: Settings → Identities → +

Forwarding

If you want mail from a mailbox automatically sent to another address (e.g. a private address, another domain):

In Plesk: Mailbox → Forwarding → +:

• enter the target address
• forward only or keep a copy and forward

With “keep a copy” enabled: the mail sits in the Plesk mailbox and gets forwarded.

Use cases

• Personal: forward work mail to a private address during vacation
• External collaborators: automatically pass mail through to external advisors (e.g. your tax accountant)
• Mailbox handover: the mailbox owner changes — enter the new address, forward the old one during the transition

Careful: forwarding triggers SPF problems

If you receive a mail from outside and forward it automatically:

• the original sender IP isn’t yours
• the receiving server checks SPF — it can fail
• the mail may land in the recipient’s spam

Workaround: SRS (Sender Rewriting Scheme) — Plesk does this by default. Still: use forwarding sparingly.

Auto-responder (out of office)

In Plesk: Mailbox → Auto-Reply → enable:

• Subject of the auto-reply (e.g. “Out of office until 15.07.”)
• Body of the reply
• Optional attachment
• Sending: once per sender or on every mail
• Anti-loop: protection against the auto-reply getting into an endless loop with other auto-reply mailboxes
• Active from / to: date control

Enable it — Plesk automatically replies to senders during that period.

Pitfall: auto-replies to spam

With auto-reply enabled, you also reply to spam mails. That confirms to spammers that your address is active → more spam.

Solution: Plesk filters spam before the auto-reply by default. If problems persist: tighten the spam settings.

Catch-all mailbox

As mentioned in Creating a mailbox: catch-all collects all mail to your domain that has no specific mailbox.

In Plesk: Domain → Mail → Mail Settings → catch-all address.

Options:

• Disable catch-all (default, recommended)
• Deliver to address: all mail to unknown addresses → a specific mailbox
• Reject all mail: bounce mail to the sender

From our experience: catch-all collects massive amounts of spam (spammers systematically try random addresses). Only enable it if you can go through it regularly.

Spam filter

Plesk uses SpamAssassin as its standard spam filter:

• incoming mail is scanned
• a score based on heuristics (words, headers, sender reputation)
• mail above the threshold lands in the Spam folder

In Mailbox → Spam Filter you can:

• set the threshold (default: 7.0)
• whitelist/blacklist
• auto-cleanup of the spam folder (delete old spam after 7 days)

The default settings are usually enough. If you have spam problems, a stricter threshold (e.g. 5.0) — but that can bring false positives.

Antivirus filter

Plesk mail uses ClamAV as its antivirus. Incoming mail carrying malware is blocked.

On by default. Nothing to configure.

For specific needs (e.g. internal file handovers with packed ZIPs that ClamAV flags as suspicious): whitelisting is possible on request.

Mail backup

Mailbox contents are included in the normal Plesk backup (daily, 7 days). More in Creating backups and restoring.

For your own mail backup (e.g. before deleting a mailbox): save the mail locally via an IMAP client.

Example setups

Freelancer with an info@ main mailbox

• Mailbox: info@deinedomain.de
• Aliases: kontakt@, hello@, support@, ich@
• Forwarding: optionally to a private address

Club board

• Mailbox: vorstand@deinverein.de
• Aliases: praesident@, schatzmeister@, schriftfuehrer@
• When the board changes: move the aliases, the mailbox stays

Family mail addresses

• One mailbox per family member (mike@, petra@, kind1@)
• Catch-all on mom: all the “odd” addresses land with her
• Auto-reply for vacation

Frequently asked questions

How many aliases per mailbox? Practically unlimited. The plan limit only applies to real mailboxes.

Can aliases point to other domains? Within your Plesk plan: yes, if you have several domains. To external domains: not directly — use forwarding for that.

A mail address with special characters (info+spam@)? Plus addressing is supported — info+spam@deinedomain.de lands at info@. Handy for spam tracking.

Auto-reply multiple times per day to the same sender? Plesk filters: one sender gets an auto-reply every 24 hours, not every mail is answered (anti-loop).

Can I write mail filters myself with Sieve? Yes, in Roundcube → Settings → Filters → code editor. Sieve is a standard.

What about mailboxes with the same name on different domains? No problem: info@domain-a.de and info@domain-b.de are completely separate.

Seeing mail logs — who sent what and when? Plesk → Statistics → Mail Statistics. Detailed mail logs are available via ticket on request.

What’s next

• Creating a mailbox
• Webmail with Roundcube
• Migrating mail accounts to xaweho