diff --git a/apps/ops/src/api/campaigns.js b/apps/ops/src/api/campaigns.js
index 564e3cf..cc53535 100644
--- a/apps/ops/src/api/campaigns.js
+++ b/apps/ops/src/api/campaigns.js
@@ -94,6 +94,16 @@ export function revokeGift (campaignId, rowIndex) {
   )
 }
 
+// Re-attempt a single failed recipient — resets status pending and
+// fires the worker. Used for one-off failures the auto-retry didn't
+// recover (rare transient Mailjet socket closes, etc.).
+export function retryRecipient (campaignId, rowIndex) {
+  return hubFetch(
+    `/campaigns/${encodeURIComponent(campaignId)}/recipients/${rowIndex}/retry`,
+    { method: 'POST' },
+  )
+}
+
 // Build the URL the browser hits to download the per-recipient CSV report
 // (giftbit shortlink ↔ email ↔ name ↔ status). The hub serves it with the
 // proper Content-Disposition so an <a download> click triggers a save.
diff --git a/apps/ops/src/modules/campaigns/pages/CampaignDetailPage.vue b/apps/ops/src/modules/campaigns/pages/CampaignDetailPage.vue
index 4c25453..4140213 100644
--- a/apps/ops/src/modules/campaigns/pages/CampaignDetailPage.vue
+++ b/apps/ops/src/modules/campaigns/pages/CampaignDetailPage.vue
@@ -105,7 +105,13 @@
       </template>
       <template v-slot:body-cell-error="props">
         <q-td :props="props">
-          <span v-if="props.row.error" class="text-negative text-caption">{{ props.row.error }}</span>
+          <div v-if="props.row.error" class="row items-center q-gutter-xs">
+            <span class="text-negative text-caption" style="max-width:240px;word-break:break-word">{{ props.row.error }}</span>
+            <q-btn v-if="props.row.status === 'failed'" flat dense size="xs" color="primary"
+                   icon="refresh" @click="retryFailedRow(props.row)">
+              <q-tooltip>Renvoyer ce destinataire (réessaie l'envoi SMTP avec 3 tentatives)</q-tooltip>
+            </q-btn>
+          </div>
         </q-td>
       </template>
     </q-table>
@@ -121,7 +127,7 @@
 import { ref, computed, onMounted, onBeforeUnmount } from 'vue'
 import { useRoute } from 'vue-router'
 import { useQuasar } from 'quasar'
-import { getCampaign, sendCampaign, campaignSseUrl, campaignReportCsvUrl } from 'src/api/campaigns'
+import { getCampaign, sendCampaign, campaignSseUrl, campaignReportCsvUrl, retryRecipient } from 'src/api/campaigns'
 
 const route = useRoute()
 const $q = useQuasar()
@@ -224,6 +230,20 @@ async function relaunch () {
   }
 }
 
+// Re-send a single failed recipient. The hub resets status pending and
+// re-fires the worker which retries up to 3 times with backoff. UI live
+// updates via the SSE channel — no manual reload needed.
+async function retryFailedRow (row) {
+  const rowIdx = (campaign.value?.recipients || []).indexOf(row)
+  if (rowIdx < 0) return
+  try {
+    await retryRecipient(id, rowIdx)
+    $q.notify({ type: 'positive', message: `Renvoi en cours pour ${row.firstname || row.email}…` })
+  } catch (e) {
+    $q.notify({ type: 'negative', message: 'Renvoi impossible : ' + e.message })
+  }
+}
+
 onMounted(async () => {
   await load()
   // Auto-subscribe to SSE if still running (or about to run)
diff --git a/services/targo-hub/lib/campaigns.js b/services/targo-hub/lib/campaigns.js
index 80efdb7..73259f0 100644
--- a/services/targo-hub/lib/campaigns.js
+++ b/services/targo-hub/lib/campaigns.js
@@ -1156,31 +1156,48 @@ async function sendCampaignAsync (id) {
       const customId = `${id}:${i}`
       r.mailjet_custom_id = customId
 
-      // email.sendEmail returns the nodemailer info object on success
-      // (truthy, with .messageId), or `false` on failure (error logged in
-      // lib/email.js). It doesn't throw. We treat falsy = failed.
-      let sendRes
-      try {
-        sendRes = await email.sendEmail({
-          to,
-          subject: p.subject || 'Un cadeau pour toi, de la part de TARGO',
-          html,
-          from: p.from || cfg.MAIL_FROM,
-          headers: { 'X-MJ-CustomID': customId },
-        })
-      } catch (e) {
-        sendRes = false
-        r.error = String(e.message || e).slice(0, 500)
+      // Auto-retry: most SMTP failures in this campaign (we observed
+      // "Unexpected socket close" once per ~200 sends) are transient
+      // Mailjet connection hiccups. Retry up to 2 times with backoff
+      // before marking the recipient as failed. The retry doesn't
+      // require any operator action and adds at most ~10s to the run.
+      const RETRY_BACKOFF_MS = [2000, 5000]
+      let sendRes = null
+      let lastErrMessage = null
+      const attempts = 1 + RETRY_BACKOFF_MS.length
+      for (let attempt = 1; attempt <= attempts; attempt++) {
+        try {
+          sendRes = await email.sendEmail({
+            to,
+            subject: p.subject || 'Un cadeau pour toi, de la part de TARGO',
+            html,
+            from: p.from || cfg.MAIL_FROM,
+            headers: { 'X-MJ-CustomID': customId },
+          })
+        } catch (e) {
+          sendRes = false
+          lastErrMessage = String(e.message || e)
+        }
+        if (sendRes && sendRes.messageId !== undefined) break  // success
+        // Falsy return — pick up the real reason from email.js side-channel
+        const le = email.getLastError && email.getLastError()
+        if (le) lastErrMessage = String(le.message || le).slice(0, 500)
+        if (attempt < attempts) {
+          log(`campaign ${id} recipient ${i} attempt ${attempt} failed (${lastErrMessage || 'unknown'}); retry in ${RETRY_BACKOFF_MS[attempt - 1]}ms`)
+          await new Promise(rs => setTimeout(rs, RETRY_BACKOFF_MS[attempt - 1]))
+        }
       }
       if (sendRes && sendRes.messageId !== undefined) {
         r.mailjet_uuid = sendRes.messageId || null   // SMTP Message-ID for reference
         r.status = 'sent'
         r.sent_at = new Date().toISOString()
         r.error = null
+        r.retry_count = attempts - 1  // 0 means first attempt succeeded
       } else {
         r.status = 'failed'
-        if (!r.error) r.error = 'SMTP send returned false (see hub logs)'
-        log(`campaign ${id} recipient ${i} failed:`, r.error)
+        r.error = lastErrMessage || 'SMTP send failed (no detail available)'
+        r.retry_count = RETRY_BACKOFF_MS.length
+        log(`campaign ${id} recipient ${i} failed after ${attempts} attempts:`, r.error)
       }
 
       saveCampaign(campaign)
@@ -2078,6 +2095,35 @@ async function handle (req, res, method, path) {
     return json(res, 202, { id, status: 'sending' })
   }
 
+  // POST /campaigns/:id/recipients/:row/retry — reset a single failed
+  // recipient back to "pending" and re-fire the worker so it picks the
+  // row up on the next pass. Used by the "Renvoyer" button in the UI
+  // for one-off transient failures that didn't recover via auto-retry.
+  const retryMatch = path.match(/^\/campaigns\/([^/]+)\/recipients\/(\d+)\/retry$/)
+  if (retryMatch && method === 'POST') {
+    const id = retryMatch[1]
+    const c = loadCampaign(id)
+    if (!c) return json(res, 404, { error: 'not found' })
+    const i = parseInt(retryMatch[2], 10)
+    const r = (c.recipients || [])[i]
+    if (!r) return json(res, 404, { error: 'recipient not found' })
+    if (r.status !== 'failed') return json(res, 400, { error: `recipient status is "${r.status}", only "failed" can be retried` })
+    if (activeWorkers.has(id)) return json(res, 409, { error: 'campaign worker already running' })
+    r.status = 'pending'
+    r.error = null
+    // Clear the previous retry counter so the new attempt gets its own 3
+    // retries inside the worker. Keep mailjet_uuid in case it WAS partially
+    // accepted by Mailjet — we'll overwrite on a successful resend.
+    r.retry_count = 0
+    // Also force the global campaign status back to 'sending' so the UI
+    // counter strip refreshes.
+    if (c.status === 'completed' || c.status === 'failed') c.status = 'sending'
+    saveCampaign(c)
+    sse.broadcast(`campaign:${id}`, 'recipient-update', { i, recipient: r })
+    setImmediate(() => sendCampaignAsync(id))
+    return json(res, 202, { id, row: i, status: 'pending' })
+  }
+
   // DELETE /campaigns/:id — remove the campaign JSON from disk. Mostly for
   // cleaning up test/draft runs; the gifts themselves live on Giftbit and
   // are unaffected. Refuses to delete while the send worker is active for
diff --git a/services/targo-hub/lib/email.js b/services/targo-hub/lib/email.js
index 4056725..056aa75 100644
--- a/services/targo-hub/lib/email.js
+++ b/services/targo-hub/lib/email.js
@@ -3,6 +3,14 @@ const cfg = require('./config')
 const { log } = require('./helpers')
 
 let _transporter = null
+// Side-channel for the most recent send failure. Callers that need the
+// specific reason (e.g. campaign worker that wants to display it in the
+// UI) read this after a falsy return from sendEmail. Cleared at the
+// start of every send call. NOT thread-safe — fine for the worker's
+// sequential loop, but if we ever parallelise sends we'd need a proper
+// returned result tuple instead.
+let _lastError = null
+function getLastError () { return _lastError }
 
 function getTransporter () {
   if (_transporter) return _transporter
@@ -40,8 +48,10 @@ function getTransporter () {
  * @returns {Promise<boolean>} true if sent
  */
 async function sendEmail (opts) {
+  _lastError = null
   const transport = getTransporter()
   if (!transport) {
+    _lastError = new Error('No transport available (SMTP not configured)')
     log('Cannot send email — no transport available')
     return false
   }
@@ -74,11 +84,11 @@ async function sendEmail (opts) {
     // callers continue to work because the object is truthy.
     return info || { messageId: null }
   } catch (e) {
+    _lastError = e
     log(`Email send failed to ${opts.to}: ${e.message}`)
     // Legacy contract: return false on failure. New callers that need the
-    // error string should check `Promise.allSettled` style or wrap in try
-    // (we don't throw here to preserve existing `if (await sendEmail(...))`
-    // call sites). The error is logged above.
+    // error string should call email.getLastError() right after a falsy
+    // return — set above, cleared at the start of every send call.
     return false
   }
 }
@@ -129,4 +139,4 @@ async function sendQuotationEmail (opts) {
   })
 }
 
-module.exports = { sendEmail, sendQuotationEmail }
+module.exports = { sendEmail, sendQuotationEmail, getLastError }