diff --git a/doc/WinFsp-Tutorial.asciidoc b/doc/WinFsp-Tutorial.asciidoc
index bf2c20a6..b792f6b6 100644
--- a/doc/WinFsp-Tutorial.asciidoc
+++ b/doc/WinFsp-Tutorial.asciidoc
@@ -538,7 +538,8 @@ static NTSTATUS GetFileInfoInternal(HANDLE Handle, FSP_FSCTL_FILE_INFO *FileInfo
     FileInfo->LastAccessTime = ((PLARGE_INTEGER)&ByHandleFileInfo.ftLastAccessTime)->QuadPart;
     FileInfo->LastWriteTime = ((PLARGE_INTEGER)&ByHandleFileInfo.ftLastWriteTime)->QuadPart;
     FileInfo->ChangeTime = FileInfo->LastWriteTime;
-    FileInfo->IndexNumber = 0;
+    FileInfo->IndexNumber =
+        ((UINT64)ByHandleFileInfo.nFileIndexHigh << 32) | (UINT64)ByHandleFileInfo.nFileIndexLow;
     FileInfo->HardLinks = 0;
 
     return STATUS_SUCCESS;
diff --git a/tst/passthrough/passthrough.c b/tst/passthrough/passthrough.c
index 0ba05ee9..c0c4122b 100644
--- a/tst/passthrough/passthrough.c
+++ b/tst/passthrough/passthrough.c
@@ -62,7 +62,8 @@ static NTSTATUS GetFileInfoInternal(HANDLE Handle, FSP_FSCTL_FILE_INFO *FileInfo
     FileInfo->LastAccessTime = ((PLARGE_INTEGER)&ByHandleFileInfo.ftLastAccessTime)->QuadPart;
     FileInfo->LastWriteTime = ((PLARGE_INTEGER)&ByHandleFileInfo.ftLastWriteTime)->QuadPart;
     FileInfo->ChangeTime = FileInfo->LastWriteTime;
-    FileInfo->IndexNumber = 0;
+    FileInfo->IndexNumber =
+        ((UINT64)ByHandleFileInfo.nFileIndexHigh << 32) | (UINT64)ByHandleFileInfo.nFileIndexLow;
     FileInfo->HardLinks = 0;
 
     return STATUS_SUCCESS;