diff --git a/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/MainActivity.kt b/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/MainActivity.kt
index b8c032a5..69a27267 100644
--- a/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/MainActivity.kt
+++ b/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/MainActivity.kt
@@ -159,25 +159,42 @@ fun TssPartyApp(
                     val expectedLength = jsonBytes.size
                     android.util.Log.d("MainActivity", "[EXPORT-FILE] Writing $expectedLength bytes...")
 
-                    // 写入文件
-                    context.contentResolver.openOutputStream(targetUri)?.use { outputStream ->
-                        outputStream.write(jsonBytes)
-                        outputStream.flush()  // 确保数据真正写入存储
-                        android.util.Log.d("MainActivity", "[EXPORT-FILE] Write and flush completed")
-                    } ?: throw Exception("无法创建输出流")
+                    // 写入文件（显式检查流创建）
+                    val outputStream = context.contentResolver.openOutputStream(targetUri)
+                        ?: throw Exception("无法创建输出流 - 可能是权限问题或存储已满")
 
-                    // 验证写入完整性
+                    outputStream.use {
+                        it.write(jsonBytes)
+                        it.flush()  // 确保数据真正写入存储
+                        android.util.Log.d("MainActivity", "[EXPORT-FILE] Write and flush completed")
+                    }
+
+                    // 验证写入完整性（显式检查流创建）
                     android.util.Log.d("MainActivity", "[EXPORT-FILE] Verifying file integrity...")
-                    context.contentResolver.openInputStream(targetUri)?.use { inputStream ->
-                        val writtenContent = inputStream.bufferedReader().readText()
+                    val inputStream = context.contentResolver.openInputStream(targetUri)
+                        ?: throw Exception("无法读取已写入的文件 - 文件可能未创建")
+
+                    inputStream.use {
+                        val writtenContent = it.bufferedReader().readText()
+                        android.util.Log.d("MainActivity", "[EXPORT-FILE] Read back ${writtenContent.length} bytes")
+
+                        // 首先检查文件是否为空（0字节）
+                        if (writtenContent.isEmpty()) {
+                            throw Exception("文件为空 (0 字节) - 写入失败")
+                        }
+
+                        // 检查长度是否匹配
                         if (writtenContent.length != json.length) {
                             throw Exception("文件长度不匹配: 期望 ${json.length}, 实际 ${writtenContent.length}")
                         }
+
+                        // 检查内容是否完全一致
                         if (writtenContent != json) {
-                            throw Exception("文件内容校验失败")
+                            throw Exception("文件内容校验失败 - 数据损坏")
                         }
-                        android.util.Log.d("MainActivity", "[EXPORT-FILE] Integrity verification passed")
-                    } ?: throw Exception("无法读取已写入的文件进行验证")
+
+                        android.util.Log.d("MainActivity", "[EXPORT-FILE] Integrity verification passed: ${writtenContent.length} bytes, content matches")
+                    }
 
                     // 验证通过
                     writeSucceeded = true