diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3b25a4b..b2be072 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# v10.1.1
+- Fix `GDTCORFlatFileStorage` crash.
+  ([firebase-ios-sdk/#14645](https://github.com/firebase/firebase-ios-sdk/issues/14645))
+
 # v10.1.0
 - Fix `[FBLPromise HTTPBody]` SwiftUI Previews crash when using binary
   distribution. ([firebase-ios-sdk/#13318](https://github.com/firebase/firebase-ios-sdk/issues/13318),
diff --git a/GoogleDataTransport/GDTCORLibrary/GDTCORPlatform.m b/GoogleDataTransport/GDTCORLibrary/GDTCORPlatform.m
index 0729bde..549b74a 100644
--- a/GoogleDataTransport/GDTCORLibrary/GDTCORPlatform.m
+++ b/GoogleDataTransport/GDTCORLibrary/GDTCORPlatform.m
@@ -232,28 +232,32 @@ GDTCORNetworkMobileSubtype GDTCORNetworkMobileSubTypeMessage(void) {
 }
 
 BOOL GDTCORWriteDataToFile(NSData *data, NSString *filePath, NSError *_Nullable *outError) {
-  BOOL result = NO;
-  if (filePath.length > 0) {
-    result = [[NSFileManager defaultManager]
-              createDirectoryAtPath:[filePath stringByDeletingLastPathComponent]
-        withIntermediateDirectories:YES
-                         attributes:nil
-                              error:outError];
-    if (result == NO || *outError) {
-      GDTCORLogDebug(@"Attempt to create directory failed: path:%@ error:%@", filePath, *outError);
-      return result;
-    }
+  if (filePath.length == 0) {
+    return NO;
   }
-
-  if (filePath.length > 0) {
-    result = [data writeToFile:filePath options:NSDataWritingAtomic error:outError];
-    if (result == NO || *outError) {
-      GDTCORLogDebug(@"Attempt to write archive failed: path:%@ error:%@", filePath, *outError);
-    } else {
-      GDTCORLogDebug(@"Writing archive succeeded: %@", filePath);
+  NSString *directoryPath = [filePath stringByDeletingLastPathComponent];
+  NSFileManager *fileManager = [NSFileManager defaultManager];
+  if (![fileManager fileExistsAtPath:directoryPath]) {
+    NSError *error = nil;
+    if (![fileManager createDirectoryAtPath:directoryPath
+                withIntermediateDirectories:YES
+                                 attributes:nil
+                                      error:&error]) {
+      GDTCORLogDebug(@"Attempt to create directory failed: path:%@ error:%@", directoryPath, error);
+      if (outError) {
+        *outError = error;
+      }
+      return NO;
     }
   }
 
+  BOOL result = [data writeToFile:filePath options:NSDataWritingAtomic error:outError];
+  if (result == NO) {
+    GDTCORLogDebug(@"Attempt to write archive failed: path:%@ error:%@", filePath,
+                   outError ? *outError : nil);
+  } else {
+    GDTCORLogDebug(@"Writing archive succeeded: %@", filePath);
+  }
   return result;
 }
 
diff --git a/GoogleDataTransport/GDTCORTests/Unit/GDTCORPlatformTest.m b/GoogleDataTransport/GDTCORTests/Unit/GDTCORPlatformTest.m
index bda2ee6..d7181d8 100644
--- a/GoogleDataTransport/GDTCORTests/Unit/GDTCORPlatformTest.m
+++ b/GoogleDataTransport/GDTCORTests/Unit/GDTCORPlatformTest.m
@@ -78,4 +78,26 @@ - (void)testGDTCORApplicationBeginBackgroundTask {
   XCTAssertNoThrow([application endBackgroundTask:bgID]);
 }
 
+- (void)testGDTCORWriteDataToFile {
+  NSString *directoryPath =
+      [NSTemporaryDirectory() stringByAppendingPathComponent:@"testGDTCORWriteDataToFile"];
+  NSString *filePath = [directoryPath stringByAppendingPathComponent:@"testFile.txt"];
+  NSData *data = [@"testData" dataUsingEncoding:NSUTF8StringEncoding];
+
+  // Clean up any old test artifacts.
+  [[NSFileManager defaultManager] removeItemAtPath:directoryPath error:nil];
+
+  // Write the data to the file.
+  NSError *error;
+  XCTAssertTrue(GDTCORWriteDataToFile(data, filePath, &error));
+  XCTAssertNil(error);
+
+  // Verify that the file was created and contains the correct data.
+  NSData *readData = [NSData dataWithContentsOfFile:filePath];
+  XCTAssertEqualObjects(data, readData);
+
+  // Clean up the test artifacts.
+  [[NSFileManager defaultManager] removeItemAtPath:directoryPath error:nil];
+}
+
 @end