Safe Mode protects you while you are migrating. The silent import lock protects you forever afterwards.
The problem it solves:
Imagine you import fifty thousand people into a list, then a month later you build a welcome sequence that triggers on joining that list. Without protection, some tools would treat those historic imports as fresh signups and start emailing them a welcome series. That is how sender reputations get destroyed.
What the lock does:
Every subscriber created by an import or a sync is permanently flagged. A flagged subscriber cannot:
- Be automatically enrolled into any sequence
- Receive a welcome email when added to a list
- Receive a double opt-in confirmation request
They can still receive broadcasts you deliberately send. That is a decision you make, not an automatic trigger, so it is allowed.
Crucially, this flag survives Safe Mode being switched off. The two protections are independent.
Which records get flagged:
Anything created by a CSV import, by the bulk add subscribers tool, or by one of the add on syncs. Someone who fills in one of your forms on your website is a genuine new signup and is never flagged.
Seeing who is locked:
The Safety tab shows how many subscribers carry the lock, with a breakdown by where they came from. The Lists tab shows a per list count in the Auto flow lock column.
Lifting it:
When you are ready for a migrated list to take part in automation, click Lift on that list. It clears the flag for everyone in that list at once. Existing sequences do not retroactively enrol them; the lift only affects what happens from that point forward.