Good, with 3 things to fix

mercadolibre.com.ar scored 76/100 (grade B). The main issues are DKIM key shorter than 2048 bits and external DMARC report address is not authorized, plus 1 more. Detected senders: Google Workspace and Zendesk.

Checked 2026-10-04 02:20 UTC · fresh check

2 passed3 need attention0 failing3 for informationDetected senders: Google Workspace, Zendesk

Fix this firstThe change with the biggest effect

Reduce SPF DNS lookups

Evaluating SPF for mercadolibre.com.ar takes 8 DNS lookups including nested includes; receivers stop at 10 and fail SPF. No detected sending service accounts for these includes; remove each one you no longer send through: spfa.mercadolibre.com.ar. Changes: Added include:_spf.google.com for Google Workspace. Added include:mail.zendesk.com for Zendesk. Replaced ~all with -all so mail from servers not listed is rejected.

TypeTXT

Name / Host

mercadolibre.com.ar

Some DNS providers want “@” here instead of the full domain.

Value

v=spf1 exists:%{i}._spf.mta.salesforce.com include:spfa.mercadolibre.com.ar ip4:172.217.128.0/19 ip4:172.217.160.0/20 ip4:172.217.192.0/19 ip4:18.211.176.124 ip4:184.73.44.157 ip4:35.190.247.0/24 ip4:64.233.160.0/19 include:_spf.google.com include:mail.zendesk.com -all

Replaces

v=spf1 exists:%{i}._spf.mta.salesforce.com include:spfa.mercadolibre.com.ar ip4:172.217.128.0/19 ip4:172.217.160.0/20 ip4:172.217.192.0/19 ip4:18.211.176.124 ip4:184.73.44.157 ip4:35.190.247.0/24 ip4:64.233.160.0/19 ~all

How to apply it

Sign in where your domain’s DNS is managed. This is often where you bought the domain, such as Cloudflare, GoDaddy or Namecheap.
Find the existing TXT record with that name and replace its value.
Save, then come back and re-check. DNS changes can take up to a few hours to show.

All checks

MXCan servers find your inbox?No issues foundPass

Nothing to report.

SPFWho may send as you?SPF is close to the 10-lookup limitNeeds attention

Warning: SPF is close to the 10-lookup limit
Evaluating the SPF record for mercadolibre.com.ar needs 8 of the 10 allowed DNS lookups. Adding one more service, or a provider growing its own record, will break SPF.
How to fix this
Info: SPF ends in softfail (~all)
"~all" is common and works well with DMARC. "-all" is stricter; switch when you are sure every sender is listed.

DKIMAre your emails signed?DKIM key shorter than 2048 bitsNeeds attention

Warning: DKIM key shorter than 2048 bits
google (1024-bit), s2 (1024-bit) uses an RSA key below 2048 bits. Short keys can be factored and some receivers treat them as weak. Rotate to a 2048-bit key at your sending provider.
Pass: DKIM key published
mercadolibre.com.ar publishes a DKIM key under google, s1, s2.

DMARCWhat happens to fakes?External DMARC report address is not authorizedNeeds attention

Warning: External DMARC report address is not authorized
Reports go to mercadolibre.com, which is outside mercadolibre.com.ar. RFC 7489 requires that domain to publish a valid v=DMARC1 TXT record at mercadolibre.com.ar._report._dmarc.mercadolibre.com; without it receivers will not send you aggregate reports. Your report provider normally publishes this for you.
Info: DMARC uses strict alignment
With adkim=s or aspf=s the DKIM d= domain or the bounce domain must equal the From domain exactly; a subdomain is not enough. Third-party senders that sign or bounce from a subdomain (or their own domain) will then fail DMARC unless they are configured to use your exact domain.

AlignmentDoes it match your From?SPF alignment depends on a custom Return-PathInfo

Info: SPF alignment depends on a custom Return-Path
This is a heuristic. Your SPF record only authorizes third-party senders (mail.zendesk.com). By default they bounce from their own Return-Path domain, and SPF then passes for that domain, not mercadolibre.com.ar. Even relaxed alignment needs the Return-Path's organizational domain to be mercadolibre.com.ar, so set up a custom Return-Path (bounce) domain under mercadolibre.com.ar with each provider, and sign with DKIM as mercadolibre.com.ar.

BIMICan inboxes show your logo?No issues foundPass

Nothing to report.

MTA-STSIs mail to you encrypted?No MTA-STS recordInfo

Info: No MTA-STS record
No MTA-STS record at _mta-sts.mercadolibre.com.ar. MTA-STS (RFC 8461) makes sending servers require TLS and a valid certificate when delivering to you, which blocks downgrade attacks.
How to fix this

TLS-RPTWill you hear about failures?No TLS-RPT recordInfo

Info: No TLS-RPT record
No TLS reporting record at _smtp._tls.mercadolibre.com.ar. TLS-RPT (RFC 8460) tells senders where to send daily reports about failed encrypted deliveries to you.
How to fix this

Other fixes

Publish the MTA-STS recordTXT

Tells sending servers that mercadolibre.com.ar publishes an MTA-STS policy at https://mta-sts.mercadolibre.com.ar/.well-known/mta-sts.txt. Change the id whenever the policy file changes.

TypeTXT

Name / Host

_mta-sts.mercadolibre.com.ar

Some DNS providers want just “_mta-sts” here.

Value

v=STSv1; id=202610040220

Host the MTA-STS policy filepolicy-file

Serve this file over HTTPS with a valid certificate for mta-sts.mercadolibre.com.ar. It lists your MX hosts and starts in testing mode; switch to mode: enforce once TLS-RPT reports show no failures.

Location

https://mta-sts.mercadolibre.com.ar/.well-known/mta-sts.txt

Contents

version: STSv1
mode: testing
mx: aspmx.l.google.com
mx: alt1.aspmx.l.google.com
mx: alt2.aspmx.l.google.com
mx: aspmx2.googlemail.com
mx: aspmx3.googlemail.com
max_age: 604800

Set up a TLS report addressinstruction

Sending servers will report TLS failures when delivering to mercadolibre.com.ar, which you need before enforcing MTA-STS. The address must accept TLS reports; a DMARC report address does not necessarily do so.

Applies to: _smtp._tls.mercadolibre.com.ar

Pick an address that will receive TLS reports: a mailbox you read (for example tls-reports@mercadolibre.com.ar, created first) or a TLS reporting service. 2. Publish a TXT record at _smtp._tls.mercadolibre.com.ar with the value v=TLSRPTv1; rua=mailto:<that address>.