LPWSTR lpwStream = (LPWSTR)DS_STREAM_RENAME;
fRename.FileNameLength = sizeof(lpwStream);

sizeof(lpwStream) is always 8 bytes on 64-bit OS

FILE_RENAME_INFO fRename;
RtlCopyMemory(fRename.FileName, lpwStream, sizeof(lpwStream));

The FILE_RENAME_INFO.FileName buffer need to be allocated by yourself

Very strange issue here. I am implementing this as part of a larger tool and in doing testing for compatibility with x86, I have found that it fails when ran as a normal user, however succeeds when ran as an Administrator. The x64 version of course works in both medium and high integrity. This testing was done on a windows 7 VM, however I also tested the x86 version on a windows 11 VM where I encountered the same issue.

Attached is a screenshot showing the issue. Top cmd prompt is normal user, bottom is admin.

I added a GetLastError() call which returned error 123, or:

"ERROR_INVALID_NAME
123 (0x7B)
The filename, directory name, or volume label syntax is incorrect."

per MSDN. This occurs at line 26 where SetFileInformationByHandle is called.

Does anyone have any ideas here? I'd believe that there is some incompatibility issue with x86, but the fact that it suceeds as an Admin but fails as a normal user, whereas it works fine for both on x64 is throwing me for a loop.

I've compiled it with VS 2019 and tested this POC on all recent Windows versions:

PC

1. Windows 7 SP1 - File was emptied, not deleted, and program crashed
2. Windows 8.1 - File was emptied, not deleted.
3. Windows 10 LTSC - File was emptied, not deleted, and stuck at "Attempting to rename file name" for 20s. File size is zero, size on disk is still 124KB.

Server

1. Windows 2008 R2 - File was emptied, not deleted, and program crashed
2. Windows 2012 R2 - File was emptied, not deleted, and program crashed
3. Windows 2016 - File was emptied, not deleted, and stuck at "Attempting to rename file name" for 20s. File size is zero, size on disk is still 124KB.
4. Windows 2019 - File was emptied, not deleted, and stuck at "Attempting to rename file name" for 20s. File size is zero, size on disk is still 124KB.