How do I contact Videotron Postmaster and resolve bounce issues?
Matthew Whittaker
Co-founder & CTO, Suped
Published 8 Aug 2025
Updated 23 May 2026
8 min read
Summarize with
The practical contact path for Videotron Postmaster issues is abuse@videotron.ca, with postmaster@videotron.ca as a secondary attempt. For the bounce pattern 4.1.0 and AUP#EML-050, treat it as a temporary delivery failure until the evidence proves otherwise. I would not start by changing authentication records or suppressing all Videotron recipients. Start by collecting the bounce, validating your sending setup, and sending a concise ticket with the exact SMTP response.
The known outcome for this class of issue is that Videotron can correct a recipient-side mail handling error after the postmaster team reviews the bounce. That does not mean every AUP#EML-050 bounce is outside your control. It means the fastest path is a clean, evidence-led report rather than a vague request to be unblocked.
Direct answer
Primary contact: Use abuse@videotron.ca for deliverability or abuse-related bounce investigations.
Secondary contact: Try postmaster@videotron.ca if the abuse route does not respond.
Best evidence: Include the full SMTP bounce, timestamps with timezone, sender IP, sender domain, and sample recipient domains.
Likely handling: If authentication and reputation are clean, ask Videotron to check recipient-side filtering or routing.
Use the right Videotron contact
For a deliverability issue, I start with the mailbox that has the best chance of reaching the security or mail operations queue: abuse@videotron.ca. That address has been reported as responsive for Videotron bounce investigations. postmaster@videotron.ca is still worth trying because postmaster mailboxes are expected for mail domains, but it should not be the only route when messages are actively bouncing.
Use official customer routes only for account, billing, or general support paths. For mail delivery evidence, keep the technical report separate, then use Videotron support or the Videotron contact page when you need a public escalation route.
Use technical mailboxes for bounces and public support routes for escalation.
Short outreach templatetext
To: abuse@videotron.ca
Cc: postmaster@videotron.ca
Subject: Delivery issue to Videotron recipients, AUP#EML-050
Hello Videotron Postmaster team,
We are seeing temporary bounces when sending legitimate mail to
Videotron recipients. The bounce text is below.
SMTP response:
4.1.0 q3VMpDbC5P4quq3VMpnx1Z service temporarily unavailable AUP#EML-050
Sender domain: example.com
Sending IP: 203.0.113.10
Time window: 2026-05-24 09:00-11:00 UTC
Message type: opted-in transactional mail
Could you check whether this is a recipient-side mail handling issue
or a filtering decision tied to our sender IP or domain?
Thank you.
Decode the bounce first
The example bounce that matters here is temporary, not permanent. The 4.1.0 status points to a transient failure class. The phrase service temporarily unavailable supports that reading. The internal code AUP#EML-050 is the part Videotron can use to locate the rule, queue state, or error path on their side.
Observed Videotron bouncetext
4.1.0 q3VMpDbC5P4quq3VMpnx1Z service temporarily unavailable AUP#EML-050
Do not treat this like a normal hard bounce. If you suppress every affected recipient permanently, you can lose reachable subscribers because the underlying condition can be temporary or recipient-side. If you need a broader refresher, compare the response with common bounce messages before deciding whether to retry, pause, or suppress.
Part
Meaning
Action
4.1.0
Temporary
Retry carefully
Unavailable
Service issue
Collect samples
AUP#EML-050
Videotron code
Quote exactly
Read the SMTP response before changing sending behavior.
Separate recipient-side errors from sender-side problems
I split Videotron bounces into two buckets before writing the ticket. The first bucket is recipient-side handling, where the remote system has a temporary issue, a bad rule, or a mailbox routing problem. The second bucket is sender-side reputation or authentication, where your IP, domain, headers, volume, or message content gives the receiver a reason to defer mail.
Looks recipient-side
Pattern: Only Videotron recipients fail while other Canadian providers accept the same stream.
Timing: Bounces start suddenly without a new domain, IP, or campaign change.
Response: The SMTP text says temporary service unavailable rather than policy rejection.
Looks sender-side
Pattern: Multiple mailbox providers defer the same mail stream at the same time.
Authentication: SPF, DKIM, or DMARC fails on real messages sent through the affected path.
Reputation: The sending IP or domain appears on a blocklist or blacklist at the same time.
The distinction matters because the message to Videotron changes. For recipient-side evidence, ask them to check their mail handling for the affected recipients. For sender-side evidence, state what you fixed, when you fixed it, and ask whether they still see a reason to defer your mail.
Flowchart for handling a Videotron bounce from SMTP code to controlled retry.
Gather evidence before sending the ticket
A useful postmaster ticket is short, but it cannot be thin. Videotron needs enough data to find the event in logs. I include the exact SMTP response, sender IP, envelope sender, header From domain, timestamps with timezone, affected recipient domains, and whether the mail is transactional, marketing, or operational.
Send a fresh message through the same route and inspect the result before contacting them. A live email tester run gives you proof of headers, authentication, and content-level issues in the mail that would otherwise be guessed at.
Email tester
Send a real email to this address. Suped opens the report when the test is ready.
?/43tests passed
Preparing test address...
Bounce sample: Keep the full SMTP response, not only the short error displayed by your ESP.
Message sample: Save the full headers for a message that used the same domain and sending IP.
Volume context: State whether this is one recipient, one campaign, or a broad Videotron pattern.
Recent changes: List new IPs, new domains, DNS edits, template changes, and volume increases.
If the test exposes a failing signature, a broken return-path, or a mismatched header From domain, fix that before asking Videotron to investigate. A postmaster team has less reason to spend time on the case if your own evidence shows authentication failures.
Check authentication and reputation
Before I send a postmaster request, I want to know whether the sender has a clean baseline. That means the active mail path passes SPF, DKIM, and DMARC, the visible From domain has a valid policy, and the sending IP or domain is not listed on a relevant blocklist (blacklist).
Use a domain health check for a quick snapshot, then keep longer-term evidence in DMARC monitoring and blocklist monitoring. This is where Suped fits the workflow: it brings DMARC, SPF, DKIM, hosted SPF, hosted DMARC, hosted MTA-STS, SPF flattening, alerts, and blocklist visibility into one operational view.
Issue steps to fix dialog showing the issue overview, tailored fix steps, and verification action
For most teams, Suped is the stronger practical choice because it does not stop at showing failures. It detects issues, explains the fix steps, alerts you when failures rise, and gives MSPs or multi-domain teams a clean way to manage many domains without chasing DNS screenshots across clients.
Do this before asking for removal
SPF: Confirm the sending service is authorized and the SPF lookup count is below the limit.
DKIM: Confirm the live message has a valid signature for the visible sending domain.
DMARC: Confirm alignment passes and reports do not show an unknown source spike.
Reputation: Check whether the same IP or domain appears on a blocklist or blacklist.
Write a message Videotron can act on
The best postmaster message is specific and narrow. Do not ask a broad question like "why are our emails blocked?" Ask them to review a defined SMTP response for a defined sender and time window. I avoid attachments unless requested because plain text is easier to route internally and less likely to be filtered.
Evidence-first message bodytext
Hello Videotron Postmaster team,
We are seeing temporary bounces to Videotron recipients from one
legitimate mail stream. Authentication passes on current samples.
Error:
4.1.0 q3VMpDbC5P4quq3VMpnx1Z service temporarily unavailable AUP#EML-050
Sender IP: 203.0.113.10
Envelope sender: bounces@example.com
Header From: example.com
Time window: 2026-05-24 09:00-11:00 UTC
Mail type: opted-in transactional notices
Affected recipients: videotron.ca addresses only
Could you check whether AUP#EML-050 points to a recipient-side issue,
a temporary filtering rule, or a sender reputation decision?
We can provide full headers or additional samples if needed.
If the failure only affects a handful of recipients, say that. If it affects every Videotron recipient, say that too. A precise scope helps the receiver decide whether to inspect one mailbox, one MX path, one filter rule, or your sender reputation.
Keep your tone factual. Postmaster teams respond faster to clear logs than to pressure. If the first response asks for more samples, send the newest examples and do not mix unrelated providers into the same thread.
Retry without creating a new problem
Because 4.1.0 is temporary, your system can retry. The risk is retrying too aggressively and turning a temporary outage into reputation damage. I use backoff, cap retries, and pause high-volume campaign mail if the bounce rate climbs for Videotron recipients.
Transactional mail: Retry with normal backoff because the recipient still needs the message.
Marketing mail: Pause the affected segment if the issue is broad and unresolved.
Hard bounces: Suppress only when the SMTP response clearly says the address is invalid.
Post-fix test: Resume slowly and watch accepted, deferred, and bounced counts by recipient domain.
If Videotron does not respond, do not keep sending the same vague request. Re-send a shorter case summary with newer samples and a clear question. For a broader escalation pattern, the same discipline applies when dealing with an unresponsive postmaster: prove the problem, prove your side is clean, and give them exact log anchors.
Do not over-correct
A temporary Videotron bounce is no reason to delete recipients, rotate IPs, or weaken DMARC. Fix clear sender-side issues, then let the postmaster investigation and controlled retries confirm the outcome.
Views from the trenches
Best practices
Send the exact SMTP response so the receiver can search logs without guessing.
Use abuse and postmaster routes together when the provider has no clear form.
Confirm SPF, DKIM, DMARC, and blocklist status before asking for action.
Common pitfalls
Treating a 4.1.0 temporary error as a permanent invalid-address bounce.
Opening a postmaster case without timestamps, sender IPs, or full bounce text.
Retrying high-volume campaigns fast enough to create a reputation issue.
Expert tips
Quote provider-specific codes exactly because internal teams can map them to rules.
Separate Videotron-only failures from wider provider failures before escalation.
Resume mail slowly after a fix and watch bounces by recipient domain.
Marketer from Email Geeks says abuse@videotron.ca has been a workable contact route for Videotron mail delivery investigations.
2023-04-27 - Email Geeks
Marketer from Email Geeks says postmaster@videotron.ca is worth trying, but abuse@videotron.ca produced the successful response.
2023-04-27 - Email Geeks
The practical answer
Contact abuse@videotron.ca first, copy or separately try postmaster@videotron.ca, and lead with the exact bounce. For 4.1.0AUP#EML-050, do not assume the recipient address is bad. Treat it as a temporary delivery problem, validate your own authentication and reputation, then ask Videotron to check the internal code against their logs.
Suped helps with the parts you control: proving DMARC alignment, finding broken SPF or DKIM paths, detecting blocklist and blacklist issues, and turning authentication failures into concrete fix steps. That evidence makes a Videotron postmaster request easier to act on and keeps the fix focused on the real cause.
Frequently asked questions
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