diff --git a/apps/server/src/persistence/DatabaseMaintenance.test.ts b/apps/server/src/persistence/DatabaseMaintenance.test.ts
index 91a538a945d20..381b143923adf 100644
--- a/apps/server/src/persistence/DatabaseMaintenance.test.ts
+++ b/apps/server/src/persistence/DatabaseMaintenance.test.ts
@@ -1,5 +1,6 @@
 import * as NodeServices from "@effect/platform-node/NodeServices";
 import { assert, it } from "@effect/vitest";
+import * as HostProcess from "@t3tools/shared/HostProcess";
 import * as NodeSqliteClient from "@t3tools/shared/nodeSqliteClient";
 import * as Clock from "effect/Clock";
 import * as Duration from "effect/Duration";
@@ -44,6 +45,7 @@ it.layer(DatabaseMaintenance.layer.pipe(Layer.provideMerge(NodeServices.layer)))
         yield* Effect.gen(function* () {
           const sql = yield* SqlClient.SqlClient;
           yield* sql`CREATE TABLE retained_data (value TEXT)`;
+          yield* sql`INSERT INTO retained_data VALUES ('keep')`;
         }).pipe(Effect.provide(NodeSqliteClient.layer({ filename: dbPath })));
         assert.isNull((yield* maintenance.inspect(dbPath)).legacyDatabaseBytes);
 
@@ -52,21 +54,52 @@ it.layer(DatabaseMaintenance.layer.pipe(Layer.provideMerge(NodeServices.layer)))
           const sql = yield* SqlClient.SqlClient;
           yield* sql`PRAGMA journal_mode = WAL`;
           yield* sql`CREATE TABLE v1_data (value TEXT)`;
+          yield* sql`INSERT INTO v1_data VALUES ('rollback')`;
         }).pipe(Effect.provide(openLegacy));
         assert.isAbove((yield* maintenance.inspect(dbPath)).legacyDatabaseBytes ?? 0, 0);
 
         const refused = yield* Effect.gen(function* () {
           const sql = yield* SqlClient.SqlClient;
           yield* sql`SELECT value FROM v1_data`;
-          return yield* Effect.flip(maintenance.removeLegacyDatabase(dbPath));
+          const failure = yield* Effect.flip(maintenance.removeLegacyDatabase(dbPath));
+          assert.deepEqual(yield* sql`SELECT value FROM v1_data`, [{ value: "rollback" }]);
+          return failure;
         }).pipe(Effect.provide(openLegacy));
         assert.equal(refused._tag, "DatabaseInUseError");
         assert.isTrue(yield* fs.exists(legacy));
 
-        yield* maintenance.removeLegacyDatabase(dbPath);
+        yield* Effect.flatMap(DatabaseMaintenance.DatabaseMaintenance, (service) =>
+          service.removeLegacyDatabase(dbPath),
+        ).pipe(
+          Effect.provide(Layer.fresh(DatabaseMaintenance.layer)),
+          Effect.provideService(HostProcess.Platform, "win32"),
+          Effect.provideService(FileSystem.FileSystem, {
+            ...fs,
+            remove: (target, options) =>
+              Effect.gen(function* () {
+                if (target === legacy) {
+                  yield* Effect.gen(function* () {
+                    const sql = yield* SqlClient.SqlClient;
+                    yield* sql`PRAGMA busy_timeout = 0`;
+                    yield* sql`BEGIN EXCLUSIVE`;
+                    yield* sql`COMMIT`;
+                  }).pipe(Effect.provide(NodeSqliteClient.layer({ filename: legacy })));
+                  // Create sidecars after the probe closes so only Doctor can remove them.
+                  yield* fs.writeFileString(`${legacy}-wal`, "leftover WAL");
+                  yield* fs.writeFileString(`${legacy}-shm`, "leftover SHM");
+                }
+                yield* fs.remove(target, options);
+              }),
+          }),
+        );
         assert.isFalse(yield* fs.exists(legacy));
         assert.isFalse(yield* fs.exists(`${legacy}-wal`));
+        assert.isFalse(yield* fs.exists(`${legacy}-shm`));
         assert.isTrue(yield* fs.exists(dbPath));
+        yield* Effect.gen(function* () {
+          const sql = yield* SqlClient.SqlClient;
+          assert.deepEqual(yield* sql`SELECT value FROM retained_data`, [{ value: "keep" }]);
+        }).pipe(Effect.provide(NodeSqliteClient.layer({ filename: dbPath, readonly: true })));
         assert.isNull((yield* maintenance.inspect(dbPath)).legacyDatabaseBytes);
       }).pipe(Effect.scoped),
     );
diff --git a/apps/server/src/persistence/DatabaseMaintenance.ts b/apps/server/src/persistence/DatabaseMaintenance.ts
index 36dad36d90e7a..4a97e6dcace98 100644
--- a/apps/server/src/persistence/DatabaseMaintenance.ts
+++ b/apps/server/src/persistence/DatabaseMaintenance.ts
@@ -1,3 +1,4 @@
+import * as HostProcess from "@t3tools/shared/HostProcess";
 import * as NodeSqliteClient from "@t3tools/shared/nodeSqliteClient";
 import * as Context from "effect/Context";
 import * as Effect from "effect/Effect";
@@ -220,13 +221,23 @@ const make = Effect.gen(function* () {
     function* (databasePath: string) {
       const legacy = legacyPath(databasePath);
       if (!(yield* fs.exists(legacy))) return;
-      // Older servers may use this file; hold its lock and delete the database before WAL to preserve commits on failure.
-      yield* Effect.gen(function* () {
-        yield* lockExclusively(legacy);
-        for (const suffix of ["", "-wal", "-shm"]) {
-          yield* fs.remove(legacy + suffix, { force: true });
-        }
-      }).pipe(Effect.provide(NodeSqliteClient.layer({ filename: legacy })));
+      // Delete the database before WAL to preserve commits if unlink fails.
+      const removeFiles = Effect.forEach(
+        ["", "-wal", "-shm"],
+        (suffix) => fs.remove(legacy + suffix, { force: true }),
+        { discard: true },
+      );
+      const connection = NodeSqliteClient.layer({ filename: legacy });
+      if ((yield* HostProcess.Platform) === "win32") {
+        // Windows blocks unlink while any SQLite handle is open, including our own.
+        yield* lockExclusively(legacy).pipe(Effect.provide(connection));
+        yield* removeFiles;
+      } else {
+        yield* lockExclusively(legacy).pipe(
+          Effect.andThen(removeFiles),
+          Effect.provide(connection),
+        );
+      }
     },
     (effect, databasePath) =>
       effect.pipe(