diff --git a/modules/programs/lieer.nix b/modules/programs/lieer.nix
index 80993f90..5d6597c0 100644
--- a/modules/programs/lieer.nix
+++ b/modules/programs/lieer.nix
@@ -31,6 +31,10 @@ let
       ({ account = account.address; } // account.lieer.settings);
   };
 
+  activationScript = account: ''
+    $DRY_RUN_CMD mkdir -m700 -p $VERBOSE_ARG "${account.maildir.absPath}"/mail/{cur,new,tmp}
+  '';
+
   settingsOpts = {
     drop_non_existing_label = mkOption {
       type = types.bool;
@@ -288,6 +292,13 @@ in {
       programs.notmuch.new.ignore = [ "/.*[.](json|lock|bak)$/" ];
 
       home.file = listToAttrs (map configFile lieerAccounts);
+
+      # Lieer requires the maildir structure to exist before syncing will work.
+      # Normally this is done via 'gmi init', but 'gmi init' bails out if the
+      # config file alreasy exists.
+      home.activation.initLieer =
+        hm.dag.entryBetween [ "linkGeneration" ] [ "writeBoundary" ]
+        (concatMapStringsSep "\n" activationScript lieerAccounts);
     }
   ]);
 }
diff --git a/tests/modules/programs/lieer/lieer.nix b/tests/modules/programs/lieer/lieer.nix
index 5e784746..4aaa5377 100644
--- a/tests/modules/programs/lieer/lieer.nix
+++ b/tests/modules/programs/lieer/lieer.nix
@@ -20,6 +20,8 @@ with lib;
       assertFileContent home-files/Mail/hm@example.com/.gmailieer.json ${
         ./lieer-expected.json
       }
+      assertFileContains activate \
+        '$DRY_RUN_CMD mkdir -m700 -p $VERBOSE_ARG "/home/hm-user/Mail/hm@example.com"/mail/{cur,new,tmp}'
     '';
   };
 }