No. 550 5.1.1 is permanent. The address has to be corrected or created first.

Why does it look like a Microsoft bounce?

Intermedia runs Microsoft Exchange, so the codes and wording match. Intermedia’s support and HostPilot are where the fix happens.

Intermedia 550 5.1.1: recipient not found

550 5.1.1Intermedia hosted Exchange recipient not foundPermanent: retrying will not helpFrom Intermedia hosted Exchange

Typical wording

550 5.1.1 RESOLVER.ADR.RecipNotFound; not found

What it means

Intermedia’s hosted Exchange answers unknown recipients with standard Exchange wording, so the bounce usually reads like a 550 5.1.1 RESOLVER.ADR.RecipNotFound line. The enhanced code means the destination mailbox address is bad (RFC 3463). The Intermedia part shows in host names under intermedia.net or serverdata.net.

In hosted Exchange, every address the tenant receives mail for must exist as a mailbox, alias, distribution list, or contact in the tenant’s directory. Admins manage that in HostPilot. When someone leaves and their mailbox is deleted, or an alias is removed during a cleanup, mail to that address starts bouncing this way.

If the tenant recently moved to or from Intermedia, some addresses may exist only on the old platform. Mail routed by MX to Intermedia then bounces for those addresses until the migration is complete.

Likely causes

A typo or an old address for someone who left the organization.
An alias or distribution list removed in HostPilot.
A migration where some mailboxes were not created on Intermedia yet.
A secondary domain that was not added to the tenant, so addresses at it are unknown.

How to fix it

As the sender, confirm the address with the recipient through another channel.
As the tenant admin, search HostPilot for the address and recreate the alias or mailbox if it should exist.
If someone left, consider forwarding their old address to a colleague instead of deleting it right away.
After a migration, confirm every domain and alias was created on Intermedia before switching MX.

Checks that apply

Your domain or sending IP (fills in the checks below)

MX Lookup Shows whether the domain’s MX points at Intermedia now, important during or after a migration.
DNS Propagation Checks whether all public resolvers see the same MX, in case some senders still reach an old platform.

FAQ

Will a retry fix it?: No. 550 5.1.1 is permanent. The address has to be corrected or created first.
Why does it look like a Microsoft bounce?: Intermedia runs Microsoft Exchange, so the codes and wording match. Intermedia’s support and HostPilot are where the fix happens.

All 191 bounce codes