Why your mailbox keeps getting locked, and how to slow the check rate

If your VICIdial mailbox keeps getting locked by the provider, the dialer is logging in too often. The fix is to raise the Frequency Check Rate on the email account so VICIdial polls the mailbox less aggressively, and to make sure your POP3 auth mode matches what the server actually supports. This post covers both.

Why providers lock the account

Many email providers cap how many login attempts they will accept in a short window. Some will lock an account for an indeterminate amount of time after more than three login attempts in fifteen minutes. VICIdial logs in on every check, so if you check too frequently you will trip that limit and the mailbox stops accepting connections until the provider releases it.

Raise the Frequency Check Rate

The Frequency Check Rate field sets how often, in minutes, VICIdial checks the external mailbox. The fastest allowed rate is five minutes, but faster is not better here. A higher number means fewer logins and far less risk of a lockout. If your provider is locking you out, raise this number first.

How the check rate drives lockouts

The relationship is direct: the lower the check rate, the more logins per hour, the closer you get to the provider's limit.

flowchart LR
  A["Low check rate"] --> B["Frequent logins"]
  B --> C{"Over provider limit?"}
  C -->|Yes| D["Mailbox locked"]
  C -->|No| E["Mail keeps flowing"]
  F["Raise check rate"] --> G["Fewer logins"]
  G --> E

Pick the right POP3 auth mode

If your account uses POP3, the Auth Mode setting controls how VICIdial logs in. BEST is the default. It tries APOP first, then CRAM-MD5, then falls back to PASS, which sends the password in cleartext. The catch is that some servers advertise APOP or CRAM-MD5 but do not actually accept them with your credentials, and the failed attempts count toward the provider's lockout limit. If you are confident your login details are right but auth keeps failing, set the mode to PASS for that server so VICIdial stops burning attempts on a method the server will not honor.

APOP and CRAM-MD5 are worth keeping when they work because they use an MD5 checksum instead of sending your password in cleartext. The point is not to avoid them on principle, it is to stop VICIdial from repeatedly attempting a method the server quietly rejects, since every rejected handshake is another login against the provider's per-window limit.

Recovering from a lock

If the account is already locked, raising the check rate alone will not free it right away. The provider holds the lock for its own window, sometimes an indeterminate stretch, before it lets connections back in. Set the Frequency Check Rate higher first so you do not re-trip the lock the moment it clears, then wait for the provider to release the account. For a Gmail mailbox you may also need to confirm IMAP access and sign in once through a browser before VICIdial can connect again.

Once the mailbox stays clear of provider locks, mail loads on schedule and each message routes to an available Agent as a normal inbound Lead. The agent replies, picks a Disposition, and the Status (lead status) flips back to available, the same loop as an inbound call.

In short: slow the check rate, watch the per-window login limit, and match the POP3 auth mode to the server. For where the email account sits in the wider inbound setup, see the VICIdial inbound email and chat guide, and for the auth setting on its own, read the VICIdial POP3 auth mode explained. If you would rather not babysit mailbox connections at all, our managed VICIdial plans come with inbound email set up for you.