Troubleshooting ·
550 5.7.515 in Outlook: What It Means and How to Fix It?
Outlook.com bounced the email because the From domain failed a trust check. The May 2025 rule, the 5,000-a-day line, and the DNS fix.
Read articleKnow when your emailstops landing.
Keep every important email on track. Hook deliverability issues early; see what is wrong and fix problems before customers ever notice.
Delivery path, SPF, DKIM and DMARC. Free, no account needed.
68.2% of top domains publish DMARC, but 25% of those still use p=none. Only 0.7% have SPF + enforced DMARC + MTA-STS + TLS-RPT + BIMI.
What is LitInboxes, and how can you use it?
Start for free01
LitInboxes watches the records and lists that decide the inbox.
LitInboxes is deliverability monitoring. LitInboxes does not send your mail. You keep Gmail, SES, Klaviyo, or whatever you already send with. We sit beside your sender and re-check the DNS records, blocklists, and reputation that affect whether that mail is trusted.
What LitInboxes watches
- SPF, DKIM, DMARC, MTA-STS, and BIMI records
- Blocklists on the domain and the IPs it resolves to
- Domain reputation, scanned daily
If you already send email, you can use LitInboxes. You do not switch senders.
02
LitInboxes re-checks every six hours on a trial or a plan.
Add the domain you send from. Recurring checks start after you begin a trial or a paid plan. Every 6 hours LitInboxes runs a full infrastructure health check on your domains: DNS records and blocklists. A weekly digest is on by default. Email alerts on a change are something you turn on.
What you do
- Add a sending domain, then start a 14-day trial. No credit card.
- Every 6 hours LitInboxes re-checks DNS records and blocklists. That loop runs on the trial.
- Turn on email alerts if you want a notice when a check changes.
Add the domain and start the trial. Then the six-hour loop runs.
03
LitInboxes will not send or warm up.
LitInboxes does not run campaigns, manage subscriber lists, warm up inboxes, or do cold outreach. If that is the job you came to hire, a different tool will treat you better. If the job is watching auth, blocklists, and reputation, and knowing what to fix, LitInboxes is the tool.
What LitInboxes is not
- Not an ESP, newsletter builder, or CRM
- Not inbox warmup
- Not cold outreach
You can use LitInboxes to watch. You cannot use LitInboxes to send.
The dashboard
Check your email deliverability.
Every domain you monitor gets a health grade, and anything that needs your attention comes with a fix, not just a warning.
app.litinboxes.com
Dashboard
Your sending health at a glance.
3
Monitored domains
1
Needs attention
2
Open issues
0
Setup incomplete
92
30-day trend
Needs attention (1)
acme-labs.ioB · 78
Listed on 1 blocklistDMARC policy still at none
Healthy (2)
acme.com
checked 2 hours agoA · 94
northloop.co
checked 4 hours agoA · 91
Verify every address before it hurts your reputation.
Run syntax, MX, and SMTP checks on every list so you stop sending to inboxes that bounce, trap, or complain.
- 01Syntax → MX → SMTP cascade verification
- 02Catch risky roles, disposables, and catch-alls
- 03Bulk CSV import, results in minutes
- 04Clean lists protect your sender reputation
Verification run
bulk · completed
512 / 512
ana@acme.comdeliverable
sales@catchall.devrisky
mike@oldmail.netinvalid
test@tempinbox.ccinvalid
95% deliverable · 3% risky · 2% invalid · finished in 74s
Security Scan
All PassedSPFValid
DKIMValid
DMARCEnforced
Blocklists0 / 24
Rspamd score
1.2
Know before you send.
Your content is scored with Rspamd, the open-source filter many mail servers run, rule by rule. Your infrastructure is checked separately: authentication, blocklist listings, and sender configuration. Catch both before they cost you.
- SPF, DKIM, and DMARC validation
- 8 high-signal blocklists, 24 on Pro
- Rspamd content scoring, rule by rule
Never get caught off guard.
Deliverability isn't a one-time check. We continuously monitor your domains and IPs for blocklist appearances, DNS drift, DMARC failures, and reputation drops so you can react immediately.
- Automated blocklist sweeps every 6 hours
- Instant alerts by email, Slack, Discord or webhook
- Historical reputation tracking
Ready to sendA · 92+3 this week
Provider: Amazon SES|ESP verification: verified|Webhook: active
DNS & authentication
SPF, DKIM, DMARC and MTA-STS, rechecked every 6 hours.
SPF · passDKIM · passDMARC · passMTA-STS · pass
Last checked · 12 min agoMonitor activeIssues: 0
DMARC
99.2%99.2%pass rate, 30 days
912 reports · 48,120 messages
Deliveries
Healthy0.3%bounce rate, 7 days
0.02% complaint rate
Blocklists
Clean0 / 24listed
Spamhaus, Barracuda, SpamCop and 21 more
Inbox placement
96%96%inbox rate
4 tests in the last 30 days
Recent activity
Infrastructure check completed, no issues12 min ago
DMARC pass rate back above 99%6 hours ago
Delisted from Spamhaus DBL1 day ago
New DKIM selector detected and verified2 days ago
Who it's for
Six ways senders use LitInboxes.
The same monitoring underneath. What differs is the signal that breaks first, and what it costs.
Solo founders
There is no deliverability team. DNS was set up once, mail goes out from one domain, and the first alert is a friend asking if you stopped writing.
Read the use caseEcommerce brands
Receipts, shipping updates and campaigns leave from different subdomains. When one drifts, support tickets tell you before your ESP does.
Read the use caseCreators and course businesses
A launch is a two-week window with no second chance. If the list stopped receiving you months ago, the offer never got a fair test.
Read the use caseAgencies and consultants
Ten clients, ten DNS zones, no single answer to the Monday morning question: which of these is broken right now?
Read the use caseSaaS and transactional email
A filtered password reset is a churn event that looks like a product bug. Transactional email fails the way infrastructure fails: quietly.
Read the use caseHigh-volume senders
Past a few thousand messages a day, providers stop judging emails and start judging you. The numbers that decide it are published.
Read the use case
From the blog
Latest insights.
FAQ
Got questions? We've got answers.
Why are my emails going to spam even though authentication passes?
Authentication is necessary but not sufficient. A blocklist listing, a falling domain reputation, a decayed list, or content that scores badly can each land passing mail in spam. That is why the four are monitored together.
What is email deliverability monitoring?
Continuously watching the signals that decide where your mail lands: DNS authentication records, blocklist status, DMARC reports, and provider reputation, with an alert when one of them changes.
How often does LitInboxes check my domain?
Every 6 hours. Alerts fire on the change rather than on the schedule, so you hear about a new listing or an edited record instead of getting a digest you have to read.
How many blocklists does LitInboxes monitor?
8 high-signal blocklists on every plan, including Spamhaus ZEN and DBL, Barracuda, SpamCop and CBL. Pro monitors 24.
Is there a free email deliverability test?
Yes. The free email health check reads your SPF, DKIM and DMARC records and checks common DKIM selectors, with no account and no quota.
How is LitInboxes different from a DMARC-only tool?
DMARC platforms read DMARC reports and stop there. LitInboxes reads the same reports and also watches blocklists, DNS drift, Google Postmaster reputation and list quality, in one subscription from $14/mo.
How much does LitInboxes cost?
$14/mo for one monitored domain, $49/mo for five, and $99/mo for fifty. Annual billing is about two months cheaper. Every plan starts with a 14-day free trial and no credit card.
Do I need to change my DNS records to use it?
Not for monitoring: the domain name is enough. Only DMARC report ingestion needs a change, pointing the rua address in your DMARC record at the address LitInboxes gives you.
Ready to own the inbox?
Every plan starts with a 14-day free trial. No charge until the trial ends, cancel anytime.
14-day free trial · no credit card · cancel anytime