Sparkforge Email: ESP Block Detected — How to Restore Sending

By Sparkforge Support Team ·Last reviewed May 3, 2026

ESP blocks pause email sending when rejection rates exceed 5%. Fix authentication, list quality, and content; submit a support ticket with your subaccount ID and error screenshot to request reinstatement.

Sparkforge enforces an ESP Block policy to protect sender reputation when major providers — Gmail, Yahoo, Outlook — start rejecting your mail. Effective February 12, 2026, sending is automatically suspended when block rates cross defined thresholds.

What you should do now

Review your bounce classification data.
Set up SPF, DKIM, and DMARC if you haven't.
Clean your lists and improve content quality.
Monitor your ESP block rate closely.

What an ESP block is

ESP blocks happen when major providers reject mail because of:

Authentication failures (DMARC, SPF, DKIM).
Poor sender reputation.
Spam-like content.
Policy violations.
Technical configuration problems.

ESP blocks are tracked separately from regular bounces and trigger immediate sending restrictions.

Block thresholds

ESP Block Rate	Action	Duration	Block Level
3%	Warning email sent	Immediate notification	Pre-block warning
5%	Sending suspended	12 hours	1st block
3% (after 1st block)	Critical warning email	Immediate notification	Pre-2nd block warning
5% (after 1st block)	Sending suspended	24 hours	2nd block
3% (after 2nd block)	Final warning email	Immediate notification	Pre-3rd block final warning
5% (after 2nd block)	Permanent suspension	Permanent	3rd block — final

All blocks reset after 7 consecutive days with ESP block rates below 1%.

In this release, blocks are temporary — capped at 24 hours. Permanent suspension is not enforced yet.

How a block looks in your account

If sending is blocked, this banner appears at the top of the affected subaccount:

Email sending is blocked due to a high number of spam blocks from email providers.

The block protects deliverability and prevents further reputation damage with ESPs.

How to request an unblock

Permanent unblocking requires manual review by Sparkforge support.

Contact Sparkforge support.
Include in the request:
- Subaccount ID
- Screenshot of the block banner
Submit the ticket for review.

What support reviews

Email sending history
Bounce and spam complaint rates
List acquisition and sending practices

Outcome: your subaccount is either unblocked, or additional remediation is required before reinstatement. Approval is not guaranteed and depends on email best practices.

Why this matters

ESP blocks damage sender reputation permanently. Poor reputation pushes legitimate mail into spam folders, hurts deliverability for the long haul, and can take months to recover. Treat thresholds as a hard ceiling, not a target.

Frequently Asked Questions

When does the new ESP Block policy start?

February 12, 2026. Existing users get advance notification before enforcement begins.

Will my account be suspended permanently right away?

Not in this release. Blocks are capped at 24 hours. The permanent-suspension tier is documented but not enforced yet.

How do I lower my ESP block rate?

Authenticate with SPF, DKIM, and DMARC; clean your list of stale addresses; review content for spam triggers; and slow sends until block rates fall.

How long until my block resets?

Blocks reset after 7 consecutive days of maintaining ESP block rates below 1%.

What do I send to support to request reinstatement?

Subaccount ID and a screenshot of the block banner. Support reviews sending history, bounce rates, and list practices before deciding.