What causes "error-mac-limit-reached" in RocketChat/Rocket.Chat?

Check the MAC usage in Administration > Omnichannel (contacts report) for the current period

RocketChat/Rocket.Chat · error · Error

error-mac-limit-reached

error-mac-limit-reached

Error message

error-mac-limit-reached

What it means

requestTranscript runs Omnichannel.isWithinMACLimit(room) before queueing the email; when the room's contact would push the workspace past its Monthly Active Contacts allowance (an enterprise-licensed metric), the check fails and it throws Error('error-mac-limit-reached'). The same guard exists in other omnichannel entry points (e.g. takeInquiry), so any of them can surface this code.

Solutions

Check the MAC usage in Administration > Omnichannel (contacts report) for the current period
Raise the limit: upgrade the license or contact sales to increase the MAC allowance
Wait for the monthly window to reset if the spike is transient
Audit what counts as an active contact — recurring visitors reuse the same contact and do not add to the count

Defensive patterns

Strategy: try-catch

Try / catch

try {
  await requestTranscript({ rid, email, subject, user });
} catch (err) {
  if (err instanceof Error && err.message === 'error-mac-limit-reached') {
    // licensing limit: surface 'contact limit reached' to admins, do not retry this month
  } else {
    throw err;
  }
}

Prevention

Monitor MAC usage versus license allowance throughout the month and alert before the cap
Size the license tier for peak months (campaigns/seasonal traffic)
Remember the same code guards other omnichannel entry points — fix the license, not one call site

When it happens

Trigger: Requesting a transcript for a room whose visitor/contact is new this month while the workspace already reached its MAC limit for the current billing cycle.

Common situations: Workspaces on an Omnichannel license tier whose monthly active contacts cap was consumed (traffic spike, bot/campaign generating many unique visitors), or trial licenses expiring with a reduced cap.

Related errors

AI-assisted analysis of RocketChat/Rocket.Chat@2a7de45707 (2026-08-18). Data as JSON: /api/errors/5ce5a85a378289fe. Report an issue: GitHub.

Appendix: source

Thrown at apps/meteor/server/lib/omnichannel/sendTranscript.ts:244

}: {
	rid: string;
	email: string;
	subject: string;
	user: AtLeast<IUser, '_id' | 'username' | 'utcOffset' | 'name'>;
}) {
	// `v` is required by the MAC-limit check below
	const room = await LivechatRooms.findOneById(rid, { projection: { _id: 1, open: 1, transcriptRequest: 1, v: 1 } });

	if (!room?.open) {
		throw new Meteor.Error('error-invalid-room', 'Invalid room');
	}

	if (room.transcriptRequest) {
		throw new Meteor.Error('error-transcript-already-requested', 'Transcript already requested');
	}

	if (!(await Omnichannel.isWithinMACLimit(room))) {
		throw new Error('error-mac-limit-reached');
	}

	const { _id, username, name, utcOffset } = user;
	const transcriptRequest = {
		requestedAt: new Date(),
		requestedBy: {
			_id,
			username,
			name,
			utcOffset,
		},
		email,
		subject,
	};

	await LivechatRooms.setEmailTranscriptRequestedByRoomId(rid, transcriptRequest);
	return true;
}

View on GitHub (pinned to 2a7de45707)