Forwarders, aliases and autoresponders

This picks up from a Hostworld cPanel account you can already log in to.

A mailbox is a full email account that stores mail and you can sign in to. An alias is an address that delivers to another mailbox and has no storage of its own. In cPanel you implement aliases with Forwarders. Use a forwarder when you want email addressed to one name to arrive in another mailbox. Use a mailbox when you need to send, store and manage mail for that identity. Autoresponders send an automatic reply from a specific address on a schedule, for example for holidays.

Before you start

• This guide is for Hostworld shared, reseller and WordPress hosting. All steps happen in cPanel under Email.
• Decide whether you need to keep a local copy when forwarding. If you want both a copy in the original mailbox and a forward, create the mailbox first, then add the forwarder. If a forwarder shares an address with a mailbox, both receive mail.
• If you later delete the mailbox to stop the local copy, that permanently deletes all stored mail and data for the account. Back up first.
• Catch‑all addresses (the “Default Address” in cPanel) receive mail for invalid names on your domain. They tend to attract a lot of spam and can fill quotas quickly.
• Forwarding to Gmail can fail SPF checks. Unless the forwarding server rewrites the envelope sender with SRS, Gmail may treat the message as unauthenticated. DKIM can still let DMARC pass if it aligns and survives.
• Avoid mail loops. Forwarders and autoresponders can trigger each other. Exim adds headers to try to break loops, but you should still design routes to avoid them.
• Mailbox quotas matter. A full mailbox can bounce with 552 “Mailbox is full”. Suspending a mailbox disables aliases and forwarders that redirect to that suspended account.
• Filters can short‑circuit delivery and can stop an autoresponder from sending. If an autoresponder is quiet and there are no errors, check for filters that force delivery.
• Domain forwarders only handle messages that would otherwise be undeliverable on the source domain, and they override the Default Address. They do not fire if there is a matching mailbox or autoresponder.

Step 1: Choose mailbox, alias or forwarder

Pick the tool that matches your goal. You can mix them, but a clear plan avoids loops and surprises.

Step 2: If you want to keep a local copy, create the mailbox first

Explain the order before you act. In cPanel, if a forwarder shares an address with a mailbox, both receive mail. That is how you forward and retain a copy. To stop storing a local copy later, delete the mailbox. Mail will continue to forward to the destination. Deleting the mailbox permanently deletes its stored mail. Back up first.

Create the mailbox in cPanel on the Email Accounts screen. Set a sensible quota to avoid 552 “Mailbox is full” bounces.

Step 3: Add an address forwarder in cPanel

An address forwarder routes one address to another. In cPanel it is also how you implement an alias so one mailbox can receive mail addressed to several names.

1. In cPanel, open Email then Forwarders and add a new forwarder. Enter the source address on your domain.
2. Set the Destination. You can enter one address, or multiple comma‑separated addresses to fan‑out delivery to a team.
3. Save. From now on, mail to the source address will deliver to the destination list. If a mailbox of the same name exists, it will also receive a copy.

Notes and limits:

• You cannot edit an existing forwarder in cPanel. To change it, delete and recreate it.
• To stop keeping a local copy, delete the mailbox for that address. That deletion removes all stored mail for that account.
• If you suspend a destination mailbox, any aliases or forwarders that redirect to that account are disabled.

For a click‑by‑click walkthrough in our cPanel, see Forwarders, aliases and autoresponders in cPanel.

Step 4: Forward an entire domain

A domain forwarder only forwards messages that are undeliverable on the source domain. If a mailbox or autoresponder exists for the local part, the domain forwarder will not fire. Domain forwarders also override the Default Address.

1. In cPanel, open Email then Forwarders. Add a Domain Forwarder from the source domain to the target domain.
2. Understand the effect. [email protected] will forward to [email protected] only if [email protected] is not a mailbox and does not have an autoresponder.

Use this when you have retired a domain and want stray mail for non‑existent addresses to land on a parallel name at another domain. If you need forwarding for specific addresses where accounts exist, use address forwarders instead.

Step 5: Configure or avoid the Default Address (catch‑all)

The Default Address handles mail for invalid or non‑existent addresses on a domain. It can be useful during a migration but it often invites spam.

Available actions in cPanel:

• Forward to an email address or to the system account for the domain.
• Discard with error at SMTP time. This rejects the mail during the SMTP transaction, returning an error to the sender. This is generally the safest choice for invalid addresses.
• Pipe to a program. Exim will feed the message to your script.
• Discard (Not Recommended). This drops the mail without signalling an error.

Recommendations:

• Prefer “Discard with error at SMTP time” for invalid names. It keeps your quota safe and gives a clear response to the sending system.
• Avoid enabling a catch‑all long term. It can flood the destination with junk and fill quotas, which in turn can cause bounces for legitimate mail.
• If you pipe to a programme, ensure the script has a correct shebang line and 0700 permissions. If your script produces any output, Exim will generate a bounce that includes that output, which can leak internal details.
• Remember that a domain forwarder overrides the Default Address.

Step 6: Use plus addressing instead of a catch‑all

cPanel supports plus addressing. If your mailbox is [email protected] you can receive at [email protected], [email protected] and so on. cPanel can auto‑create folders for the plus addresses. This captures variants per service without opening a catch‑all to spam.

Step 7: Set a holiday or auto‑reply with Autoresponders

Autoresponders send an automatic reply from a specific address. You can set:

• A start and stop time.
• An interval in hours so the same sender does not receive repeated replies within that window.
• A subject and body for the reply.

1. In cPanel, open Email then Autoresponders. Create a responder for the address you want to reply from.
2. Set the interval. A few hours is sensible. Very low intervals can annoy senders and may trigger rate limits.
3. Set start and stop times to cover your absence.
4. Save.

Notes and cautions:

• User‑defined autoresponders in cPanel ignore messages marked as spam with a score of 5 or more.
• You can also create autoresponders from Webmail for non‑default accounts.
• Avoid loops. If two addresses have autoresponders, or you chain a forwarder to an address with an autoresponder, you can create a loop. Exim uses headers such as X‑Loop to detect and break loops, but design to avoid them.
• Do not reply to list or bulk mail. You risk sending an automatic response to many unintended recipients.
• If an autoresponder does not send and there are no errors, check for account‑level filters that force delivery or otherwise short‑circuit processing.

Step 8: Test routes with Forwarders Trace

cPanel’s Forwarders interface includes a Trace function. It shows the route a forwarded message will take and flags errors or non‑deliverable paths. Use it after you create or change forwarders, or when diagnosing misrouting.

Step 9: Be careful forwarding to Gmail. SPF, SRS and DMARC

SPF evaluates the connecting IP at the final hop. When you forward a message, the forwarder’s server connects to Gmail. Unless the forwarder rewrites the envelope sender using SRS, Gmail sees the forwarder’s IP as not authorised in the original sender’s SPF record. SPF can fail. Google’s own guidance notes that forwarded messages often fail SPF.

What helps:

• SRS on the forwarding server. Exim supports SRS in recent versions. The server must apply SRS changes to help forwarded mail pass SPF at the destination.
• DKIM and DMARC. If SPF fails but the original message’s DKIM signature survives and aligns with the visible From domain, DMARC can still pass. If DKIM is missing or mailing list software modifies the message, DMARC may fail.

What to do in practice:

• Test by sending from a domain with valid SPF and DKIM to your forwarded address and examine results in Gmail.
• If forwarded mail to Gmail is failing authentication, open a support ticket and ask us to review the server’s forwarding and SRS settings for your cPanel account.
• If reliable delivery to Gmail is essential and you see failures, prefer delivery to a mailbox that Gmail fetches indirectly over pure server‑side forwarding. If you need advice on options that fit your Hostworld plan, open a support ticket.

Step 10: Maintain, change or remove what you set up

• Change a forwarder. You cannot edit a forwarder. Delete it and recreate it with the new destination list.
• Stop keeping a local copy. Delete the mailbox that shares the address with the forwarder. Back up first. The forwarder will continue to deliver to its destination.
• Quotas and suspension. If you start seeing 552 “Mailbox is full” bounces, increase the quota or archive mail. If you suspend a mailbox, remember that aliases and forwarders to that account are also disabled.
• Review catch‑all settings. If spam or quota pressure increases, change the Default Address to “Discard with error at SMTP time”.

What next

If you are ready to configure this in our panel, follow the step‑by‑step support article: Forwarders, aliases and autoresponders in cPanel.

If you run mail on a VPS and want to learn more about server‑side email tooling, see our VPS guides. To compare plans for a new VPS in the UK, visit UK London VPS.

If you get stuck or see unexpected bounces, please open a support ticket. Tickets are routed to the right team and are tracked against your account.