diff --git a/changelog.d/984.improvements b/changelog.d/984.improvements
new file mode 100644
index 0000000000..059275f494
--- /dev/null
+++ b/changelog.d/984.improvements
@@ -0,0 +1 @@
+Modification du message d'information quand les messages sont verrouillés
\ No newline at end of file
diff --git a/library/ui-strings/src/main/res/values-fr/strings.xml b/library/ui-strings/src/main/res/values-fr/strings.xml
index e5e71dd4a5..d1f7e83164 100644
--- a/library/ui-strings/src/main/res/values-fr/strings.xml
+++ b/library/ui-strings/src/main/res/values-fr/strings.xml
@@ -1527,7 +1527,7 @@
     <string name="crypto_error_withheld_unverified">Vous ne pouvez pas accéder à ce message car l’envoyeur n’a pas confiance en votre appareil</string> <!-- Tchap: Use custom string -->
     <string name="crypto_error_withheld_blacklisted">Impossible d’accéder à ce message car vous avez été bloqué par l’envoyeur</string>
     <string name="notice_crypto_unable_to_decrypt_friendly_desc">À cause du chiffrement de bout en bout, vous pouvez avoir besoin d’attendre l’arrivée du message de quelqu’un car les clés Tchap ne vous ont pas été correctement envoyées.</string> <!-- Tchap: Use custom string -->
-    <string name="notice_crypto_unable_to_decrypt_friendly">Echec de déchiffrement : veuillez ouvrir ${app_name} sur vos autres appareils afin d’autoriser le partage de clés</string> <!-- Tchap: Use custom string -->
+    <string name="notice_crypto_unable_to_decrypt_friendly">Message verrouillé : ouvrez ${app_name} sur un autre appareil pour récupérer vos messages.</string> <!-- Tchap: Use custom string -->
     <string name="notice_crypto_unable_to_decrypt_final">Vous n’avez pas accès à ce message</string>
     <string name="room_settings_save_success">Vous avez bien changé les paramètres du salon</string>
     <string name="room_settings_topic_hint">Sujet</string>
diff --git a/library/ui-strings/src/main/res/values-fr/strings_tchap.xml b/library/ui-strings/src/main/res/values-fr/strings_tchap.xml
index 90f507a50f..91736c0d7c 100644
--- a/library/ui-strings/src/main/res/values-fr/strings_tchap.xml
+++ b/library/ui-strings/src/main/res/values-fr/strings_tchap.xml
@@ -36,6 +36,7 @@
     <string name="tchap_empty_room_no_permission_to_post">Votre destinataire a quitté le salon ou refusé votre invitation. Vous ne pouvez pas lui envoyer de message.</string>
     <string name="tchap_discovery_section">Utilisateur trouvé</string>
     <string name="tchap_login_reset_password_on">Réinitialiser le mot de passe</string>
+    <string name="tchap_notice_crypto_unable_to_decrypt_faq">Sinon, consultez la FAQ.</string>
 
     <!-- tchap discussion -->
     <string name="tchap_contact_external">Externe</string>
diff --git a/library/ui-strings/src/main/res/values/strings.xml b/library/ui-strings/src/main/res/values/strings.xml
index abf972766c..ad8abd723b 100644
--- a/library/ui-strings/src/main/res/values/strings.xml
+++ b/library/ui-strings/src/main/res/values/strings.xml
@@ -2810,7 +2810,7 @@
     <string name="room_settings_set_avatar">Set avatar</string>
 
     <string name="notice_crypto_unable_to_decrypt_final">You cannot access this message</string>
-    <string name="notice_crypto_unable_to_decrypt_friendly">Failed to decrypt: please open ${app_name} on your other devices to allow key share request</string> <!-- Tchap: Use custom string -->
+    <string name="notice_crypto_unable_to_decrypt_friendly">Locked message: please open ${app_name} on another device to retrieve your messages.</string> <!-- Tchap: Use custom string -->
     <string name="notice_crypto_unable_to_decrypt_friendly_desc">Due to end-to-end encryption, you might need to wait for someone\'s message to arrive because the encryption keys were not properly sent to you.</string>
     <string name="crypto_error_withheld_blacklisted">You cannot access this message because you have been blocked by the sender</string>
     <string name="crypto_error_withheld_unverified">You cannot access this message because your session is not trusted by the sender</string>
diff --git a/library/ui-strings/src/main/res/values/strings_tchap.xml b/library/ui-strings/src/main/res/values/strings_tchap.xml
index 10efd93c50..9aabed5a49 100644
--- a/library/ui-strings/src/main/res/values/strings_tchap.xml
+++ b/library/ui-strings/src/main/res/values/strings_tchap.xml
@@ -36,6 +36,7 @@
     <string name="tchap_empty_room_no_permission_to_post">Your recipient has left the room or has refused your invite. You cannot send him a message.</string>
     <string name="tchap_discovery_section">Discovered user</string>
     <string name="tchap_login_reset_password_on">Reset password</string>
+    <string name="tchap_notice_crypto_unable_to_decrypt_faq">Otherwise, open the FAQ.</string>
 
     <!-- tchap discussion -->
     <string name="tchap_contact_external">External</string>
diff --git a/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/factory/EncryptedItemFactory.kt b/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/factory/EncryptedItemFactory.kt
index 4bc68c10aa..13fcfa189e 100644
--- a/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/factory/EncryptedItemFactory.kt
+++ b/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/factory/EncryptedItemFactory.kt
@@ -16,11 +16,16 @@
 
 package im.vector.app.features.home.room.detail.timeline.factory
 
+import android.text.style.ClickableSpan
+import android.view.View
+import androidx.core.text.toSpannable
 import im.vector.app.R
 import im.vector.app.core.epoxy.VectorEpoxyModel
 import im.vector.app.core.resources.ColorProvider
 import im.vector.app.core.resources.DrawableProvider
 import im.vector.app.core.resources.StringProvider
+import im.vector.app.core.utils.openUrlInExternalBrowser
+import im.vector.app.core.utils.tappableMatchingText
 import im.vector.app.features.home.room.detail.timeline.helper.AvatarSizeProvider
 import im.vector.app.features.home.room.detail.timeline.helper.MessageInformationDataFactory
 import im.vector.app.features.home.room.detail.timeline.helper.MessageItemAttributesFactory
@@ -92,15 +97,18 @@ class EncryptedItemFactory @Inject constructor(
                                 }
                             }
                             else -> {
+                                // Tchap: Add faq link in unable to decrypt error
                                 span {
-                                    drawableProvider.getDrawable(R.drawable.ic_clock, colorFromAttribute)?.let {
-                                        image(it, "baseline")
-                                        +" "
-                                    }
-                                    span(stringProvider.getString(R.string.notice_crypto_unable_to_decrypt_friendly)) {
-                                        textStyle = "italic"
-                                        textColor = colorFromAttribute
-                                    }
+                                    val faq = stringProvider.getString(R.string.tchap_notice_crypto_unable_to_decrypt_faq)
+                                    text = "${stringProvider.getString(R.string.notice_crypto_unable_to_decrypt_friendly)} $faq"
+                                            .toSpannable()
+                                            .tappableMatchingText(faq, object : ClickableSpan() {
+                                                override fun onClick(widget: View) {
+                                                    openUrlInExternalBrowser(widget.context, TCHAP_FAQ_UTD_URL)
+                                                }
+                                            })
+                                    textStyle = "italic"
+                                    textColor = colorFromAttribute
                                 }
                             }
                         }
@@ -127,4 +135,9 @@ class EncryptedItemFactory @Inject constructor(
             else -> null
         }
     }
+
+    companion object {
+        private const val TCHAP_FAQ_UTD_URL =
+                "https://aide.tchap.beta.gouv.fr/fr/article/dechiffrement-impossible-de-mes-messages-comment-y-remedier-android-m6e371/"
+    }
 }