diff --git a/config/config.exs b/config/config.exs
index 78bf04dd..d2a0f921 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -113,17 +113,22 @@ config :mobilizon, :media_proxy,
 config :mobilizon, Mobilizon.Web.Email.Mailer,
   adapter: Swoosh.Adapters.SMTP,
   relay: "localhost",
-  # usually 25, 465 or 587
-  port: 25,
   username: "",
   password: "",
   # can be `:always` or `:never`
   auth: :if_available,
   # can be `true`
-  ssl: false,
+  # ssl: false,
   # can be `:always` or `:never`
   tls: :if_available,
   allowed_tls_versions: [:tlsv1, :"tlsv1.1", :"tlsv1.2"],
+  tls_options: [
+    verify: :verify_peer,
+    versions: [:"tlsv1.2", :"tlsv1.3"],
+    cacerts: :public_key.cacerts_get(),
+    server_name_indication: "localhost",
+    depth: 99
+  ],
   retries: 1,
   # can be `true`
   no_mx_lookups: false
diff --git a/config/docker.exs b/config/docker.exs
index ec238770..994c2001 100644
--- a/config/docker.exs
+++ b/config/docker.exs
@@ -50,7 +50,14 @@ config :mobilizon, Mobilizon.Web.Email.Mailer,
   username: System.get_env("MOBILIZON_SMTP_USERNAME", nil),
   password: System.get_env("MOBILIZON_SMTP_PASSWORD", nil),
   tls: :if_available,
-  allowed_tls_versions: [:tlsv1, :"tlsv1.1", :"tlsv1.2"],
+  allowed_tls_versions: [:"tlsv1.2", :"tlsv1.3"],
+  tls_options: [
+    verify: :verify_peer,
+    versions: [:"tlsv1.2", :"tlsv1.3"],
+    cacerts: :public_key.cacerts_get(),
+    server_name_indication: System.get_env("MOBILIZON_SMTP_SERVER", "localhost"),
+    depth: 99
+  ],
   ssl: System.get_env("MOBILIZON_SMTP_SSL", "false"),
   retries: 1,
   no_mx_lookups: false,
diff --git a/lib/graphql/resolvers/user.ex b/lib/graphql/resolvers/user.ex
index 73d85e0e..e08f413c 100644
--- a/lib/graphql/resolvers/user.ex
+++ b/lib/graphql/resolvers/user.ex
@@ -302,6 +302,9 @@ defmodule Mobilizon.GraphQL.Resolvers.User do
       {:error, :invalid_email} ->
         {:error, dgettext("errors", "This email doesn't seem to be valid")}
 
+      {:error, :failed_sending_mail} ->
+        {:error, dgettext("errors", "Couldn't send an email. Internal error.")}
+
       {:error, :email_too_soon} ->
         {:error,
          dgettext(
diff --git a/lib/web/email/mailer.ex b/lib/web/email/mailer.ex
index 2f78477a..90632214 100644
--- a/lib/web/email/mailer.ex
+++ b/lib/web/email/mailer.ex
@@ -4,10 +4,18 @@ defmodule Mobilizon.Web.Email.Mailer do
   """
   use Swoosh.Mailer, otp_app: :mobilizon
   alias Mobilizon.Service.ErrorReporting.Sentry
+  require Logger
 
   @spec send_email(Swoosh.Email.t()) :: {:ok, term} | {:error, term}
   def send_email(email) do
-    Mobilizon.Web.Email.Mailer.deliver(email)
+    Logger.debug(
+      "Mailer options #{inspect(Keyword.drop(Application.get_env(:mobilizon, Mobilizon.Web.Email.Mailer), [:tls_options]))}"
+    )
+
+    Logger.debug("Sending mail, #{inspect(email)}")
+    res = Mobilizon.Web.Email.Mailer.deliver(email)
+    Logger.debug("Return from sending mail #{inspect(res)}")
+    res
   rescue
     error ->
       Sentry.capture_exception(error,
diff --git a/lib/web/email/user.ex b/lib/web/email/user.ex
index d0278d7d..6967f055 100644
--- a/lib/web/email/user.ex
+++ b/lib/web/email/user.ex
@@ -91,13 +91,19 @@ defmodule Mobilizon.Web.Email.User do
            Users.update_user(user, %{
              "confirmation_sent_at" => DateTime.utc_now() |> DateTime.truncate(:second)
            }) do
-      send_confirmation_email(user, locale)
-      Logger.info("Sent confirmation email again to #{user.email}")
-      {:ok, user.email}
+      case send_confirmation_email(user, locale) do
+        {:ok, _} ->
+          Logger.info("Sent confirmation email again to #{user.email}")
+          {:ok, user.email}
+
+        {:error, err} ->
+          Logger.error("Failed sending email to #{user.email}. #{inspect(err)}")
+          {:error, :failed_sending_mail}
+      end
     end
   end
 
-  @spec send_confirmation_email(User.t(), String.t()) :: Swoosh.Email.t()
+  @spec send_confirmation_email(User.t(), String.t()) :: {:ok, term} | {:error, term}
   def send_confirmation_email(%User{} = user, locale \\ "en") do
     user
     |> Email.User.confirmation_email(locale)
diff --git a/mix.exs b/mix.exs
index f2a45055..84226289 100644
--- a/mix.exs
+++ b/mix.exs
@@ -211,7 +211,7 @@ defmodule Mobilizon.Mixfile do
       {:nimble_csv, "~> 1.1"},
       {:export, "~> 0.1.0"},
       {:erlport, "~> 0.11.0"},
-      {:tz_world, "~> 1.0"},
+      {:tz_world, "1.3.0"},
       {:tzdata, "~> 1.1"},
       {:codepagex, "~> 0.1.6"},
       {:vite_phx, "~> 0.2"},
diff --git a/mix.lock b/mix.lock
index e9804a27..84bca8c3 100644
--- a/mix.lock
+++ b/mix.lock
@@ -139,7 +139,7 @@
   "telemetry": {:hex, :telemetry, "1.2.1", "68fdfe8d8f05a8428483a97d7aab2f268aaff24b49e0f599faa091f1d4e7f61c", [:rebar3], [], "hexpm", "dad9ce9d8effc621708f99eac538ef1cbe05d6a874dd741de2e689c47feafed5"},
   "tesla": {:hex, :tesla, "1.7.0", "a62dda2f80d4f8a925eb7b8c5b78c461e0eb996672719fe1a63b26321a5f8b4e", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:exjsx, ">= 3.0.0", [hex: :exjsx, repo: "hexpm", optional: true]}, {:finch, "~> 0.13", [hex: :finch, repo: "hexpm", optional: true]}, {:fuse, "~> 2.4", [hex: :fuse, repo: "hexpm", optional: true]}, {:gun, "~> 1.3", [hex: :gun, repo: "hexpm", optional: true]}, {:hackney, "~> 1.6", [hex: :hackney, repo: "hexpm", optional: true]}, {:ibrowse, "4.4.0", [hex: :ibrowse, repo: "hexpm", optional: true]}, {:jason, ">= 1.0.0", [hex: :jason, repo: "hexpm", optional: true]}, {:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:mint, "~> 1.0", [hex: :mint, repo: "hexpm", optional: true]}, {:msgpax, "~> 2.3", [hex: :msgpax, repo: "hexpm", optional: true]}, {:poison, ">= 1.0.0", [hex: :poison, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: true]}], "hexpm", "2e64f01ebfdb026209b47bc651a0e65203fcff4ae79c11efb73c4852b00dc313"},
   "timex": {:hex, :timex, "3.7.11", "bb95cb4eb1d06e27346325de506bcc6c30f9c6dea40d1ebe390b262fad1862d1", [:mix], [{:combine, "~> 0.10", [hex: :combine, repo: "hexpm", optional: false]}, {:gettext, "~> 0.20", [hex: :gettext, repo: "hexpm", optional: false]}, {:tzdata, "~> 1.1", [hex: :tzdata, repo: "hexpm", optional: false]}], "hexpm", "8b9024f7efbabaf9bd7aa04f65cf8dcd7c9818ca5737677c7b76acbc6a94d1aa"},
-  "tz_world": {:hex, :tz_world, "1.3.1", "dedb8373fce594098909ff36d37f5e5e30e47cb40ef846d1dfc91eb39f7ebaaf", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:certifi, "~> 2.5", [hex: :certifi, repo: "hexpm", optional: true]}, {:geo, "~> 1.0 or ~> 2.0 or ~> 3.3", [hex: :geo, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "901ed2b4a4430ecab3765244da4a19e6f19141867c2ab3753924919b87ed2224"},
+  "tz_world": {:hex, :tz_world, "1.3.0", "a4d70486c7934b710f8b3b4374d62ebdd75e3d2b8914771ef6c62c3635a6088f", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:certifi, "~> 2.5", [hex: :certifi, repo: "hexpm", optional: true]}, {:geo, "~> 1.0 or ~> 2.0 or ~> 3.3", [hex: :geo, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "78b565aa0899b48ce34686319119dfdadff07a255ec43fd9ed6e7d60cc8d1390"},
   "tzdata": {:hex, :tzdata, "1.1.1", "20c8043476dfda8504952d00adac41c6eda23912278add38edc140ae0c5bcc46", [:mix], [{:hackney, "~> 1.17", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm", "a69cec8352eafcd2e198dea28a34113b60fdc6cb57eb5ad65c10292a6ba89787"},
   "ueberauth": {:hex, :ueberauth, "0.10.5", "806adb703df87e55b5615cf365e809f84c20c68aa8c08ff8a416a5a6644c4b02", [:mix], [{:plug, "~> 1.5", [hex: :plug, repo: "hexpm", optional: false]}], "hexpm", "3efd1f31d490a125c7ed453b926f7c31d78b97b8a854c755f5c40064bf3ac9e1"},
   "ueberauth_cas": {:hex, :ueberauth_cas, "2.3.1", "df45a1f2c5df8bc80191cbca4baeeed808d697702ec5ebe5bd5d5a264481752f", [:mix], [{:httpoison, "~> 1.8", [hex: :httpoison, repo: "hexpm", optional: false]}, {:sweet_xml, "~> 0.7", [hex: :sweet_xml, repo: "hexpm", optional: false]}, {:ueberauth, "~> 0.6", [hex: :ueberauth, repo: "hexpm", optional: false]}], "hexpm", "5068ae2b9e217c2f05aa9a67483a6531e21ba0be9a6f6c8749bb7fd1599be321"},
diff --git a/test/graphql/resolvers/user_test.exs b/test/graphql/resolvers/user_test.exs
index 544e6fb5..e3e1822a 100644
--- a/test/graphql/resolvers/user_test.exs
+++ b/test/graphql/resolvers/user_test.exs
@@ -121,6 +121,12 @@ defmodule Mobilizon.GraphQL.Resolvers.UserTest do
         }
   """
 
+  @resend_registration_email_mutation """
+    mutation ResendConfirmationEmail($email: String!) {
+      resendConfirmationEmail(email: $email)
+    }
+  """
+
   @send_reset_password_mutation """
     mutation SendResetPassword($email: String!) {
       sendResetPassword(email: $email)
@@ -706,22 +712,16 @@ defmodule Mobilizon.GraphQL.Resolvers.UserTest do
 
   describe "Resolver: Resend confirmation emails" do
     test "test resend_confirmation_email/3 with valid email resends an validation email",
-         context do
+         %{conn: conn} do
       {:ok, %User{} = user} = Users.register(%{email: "toto@tata.tld", password: "p4ssw0rd"})
 
-      mutation = """
-          mutation {
-            resendConfirmationEmail(
-                  email: "#{user.email}"
-              )
-            }
-      """
-
       res =
-        context.conn
-        |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
+        AbsintheHelpers.graphql_query(conn,
+          query: @resend_registration_email_mutation,
+          variables: %{email: user.email}
+        )
 
-      assert hd(json_response(res, 200)["errors"])["message"] ==
+      assert hd(res["errors"])["message"] ==
                "You requested again a confirmation email too soon. Please try again in a few minutes"
 
       # Hammer time !
@@ -730,28 +730,24 @@ defmodule Mobilizon.GraphQL.Resolvers.UserTest do
       })
 
       res =
-        context.conn
-        |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
+        AbsintheHelpers.graphql_query(conn,
+          query: @resend_registration_email_mutation,
+          variables: %{email: user.email}
+        )
 
-      assert json_response(res, 200)["data"]["resendConfirmationEmail"] == user.email
+      assert res["data"]["resendConfirmationEmail"] == user.email
       assert_email_sent(to: user.email)
     end
 
-    test "test resend_confirmation_email/3 with invalid email resends an validation email",
-         context do
-      mutation = """
-          mutation {
-            resendConfirmationEmail(
-                  email: "oh@no.com"
-              )
-            }
-      """
-
+    test "test resend_confirmation_email/3 with invalid email does not resend an validation email",
+         %{conn: conn} do
       res =
-        context.conn
-        |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
+        AbsintheHelpers.graphql_query(conn,
+          query: @resend_registration_email_mutation,
+          variables: %{email: "oh@no.com"}
+        )
 
-      assert hd(json_response(res, 200)["errors"])["message"] ==
+      assert hd(res["errors"])["message"] ==
                "No user to validate with this email was found"
     end
   end