diff --git a/gradle.properties b/gradle.properties
index ef5d45a..5ab569f 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -3,7 +3,7 @@ android.useAndroidX=true
 kotlin.code.style=official
 android.nonTransitiveRClass=true
 PUBLISH_VERSION=1.0.5
-SDK_CORE_VERSION=1.1.5
+SDK_CORE_VERSION=1.1.6-SNAPSHOT
 SDK_IM_VERSION=1.1.3
 SDK_PUSH_VERSION=1.1.3
 SDK_UPDATE_VERSION=1.1.8
diff --git a/sdk-core/src/main/java/com/xuqm/sdk/file/FileSDK.kt b/sdk-core/src/main/java/com/xuqm/sdk/file/FileSDK.kt
index 42f7326..8508ecf 100644
--- a/sdk-core/src/main/java/com/xuqm/sdk/file/FileSDK.kt
+++ b/sdk-core/src/main/java/com/xuqm/sdk/file/FileSDK.kt
@@ -160,9 +160,16 @@ object FileSDK {
         notificationTitle: String? = null,
         onProgress: (Int) -> Unit = {},
     ): File = withContext(Dispatchers.IO) {
-        val resolvedName = fileName?.takeIf { it.isNotBlank() }
+        val rawName = fileName?.takeIf { it.isNotBlank() }
             ?: downloadUrl.substringAfterLast('/').substringBefore('?').takeIf { it.isNotBlank() }
             ?: "download.bin"
+        // If the provided name has no extension, infer it from the URL path.
+        val resolvedName = if (!rawName.contains('.')) {
+            val urlExt = downloadUrl.substringAfterLast('/').substringBefore('?')
+                .substringAfterLast('.', "").lowercase()
+                .takeIf { it.isNotBlank() && it.length <= 10 && !it.contains('/') }
+            if (urlExt != null) "$rawName.$urlExt" else rawName
+        } else rawName
 
         val baseDir = when (destination) {
             FileDownloadDestination.PublicDownloads -> resolveBaseDir(context, destination)
@@ -192,6 +199,7 @@ object FileSDK {
         }
 
         val capturedNotifId = notifId
+        var downloadError: Throwable? = null
         try {
             FileTransfer.downloadToFile(downloadUrl, target) { progress ->
                 if (capturedNotifId != null) {
@@ -204,21 +212,38 @@ object FileSDK {
                 }
                 onProgress(progress)
             }
+        } catch (e: Throwable) {
+            downloadError = e
+            android.util.Log.e("FileSDK", "download failed: url=$downloadUrl dest=${target.absolutePath}", e)
+            throw e
         } finally {
             capturedNotifId?.let { id ->
                 val nm = NotificationManagerCompat.from(context)
                 nm.cancel(id)
                 if (nm.areNotificationsEnabled()) {
-                    nm.notify(
-                        id,
-                        NotificationCompat.Builder(context, DOWNLOAD_CHANNEL_ID)
-                            .setSmallIcon(android.R.drawable.stat_sys_download_done)
-                            .setContentTitle(notificationTitle)
-                            .setContentText("下载完成：$resolvedName")
-                            .setContentIntent(buildOpenFilePendingIntent(context, target))
-                            .setAutoCancel(true)
-                            .build(),
-                    )
+                    val err = downloadError
+                    if (err == null) {
+                        nm.notify(
+                            id,
+                            NotificationCompat.Builder(context, DOWNLOAD_CHANNEL_ID)
+                                .setSmallIcon(android.R.drawable.stat_sys_download_done)
+                                .setContentTitle(notificationTitle)
+                                .setContentText("下载完成：$resolvedName")
+                                .setContentIntent(buildOpenFilePendingIntent(context, target))
+                                .setAutoCancel(true)
+                                .build(),
+                        )
+                    } else {
+                        nm.notify(
+                            id,
+                            NotificationCompat.Builder(context, DOWNLOAD_CHANNEL_ID)
+                                .setSmallIcon(android.R.drawable.stat_notify_error)
+                                .setContentTitle(notificationTitle)
+                                .setContentText("下载失败：${err.message ?: resolvedName}")
+                                .setAutoCancel(true)
+                                .build(),
+                        )
+                    }
                 }
             }
         }