diff --git a/src/main/resources/strings/BriarDesktop.properties b/src/main/resources/strings/BriarDesktop.properties
index 54b537acd39bd471fae54705d15963d3d5c48050..6eace58a5b15ba58f288861c7d5dd6e221b61c7d 100644
--- a/src/main/resources/strings/BriarDesktop.properties
+++ b/src/main/resources/strings/BriarDesktop.properties
@@ -69,6 +69,16 @@ introduction.response.declined.auto=The introduction to {0} was automatically de
 introduction.response.accepted.received={0} accepted the introduction to {1}.
 introduction.response.declined.received={0} declined the introduction to {1}.
 introduction.response.declined.received_by_introducee={0} says that {1} declined the introduction.
+introduction.error.own_link=Please enter contact's link, not your own
+introduction.error.remote_invalid=Remote handshake link is invalid
+introduction.error.alias_invalid=Alias is invalid
+introduction.error.link_invalid=Link is invalid: {0}
+introduction.error.public_key_invalid=Public key is invalid: {0}
+introduction.error.adding_failed=Adding contact failed
+introduction.error.contact_already_exists=You already have a contact with this link: {0}
+introduction.error.pending_contact_already_exists=You already have a pending contact with this link: {0}
+introduction.error.duplicate_contact_explainer=Be careful if {0} is not the same person as {1}.\n\nOne of them may be trying to discover who your contacts are.\n\nDon't tell them you received the same link from someone else.
+
 
 # Private Group Sharing
 group.invitation.received={0} has invited you to join the group "{1}".