BSOD with Windows 10 and FAT32 memory sticks

[philip_katz]

Recently upgraded to Windows 10 and running FFS 7.3.

Whenever I try to sync files from my hard drive to a memory stick which is FAT32 formatted, I get an immediate BSOD (FAT_FILE_SYSTEM) after I hit the Sync button. This is reproducible across multiple memory sticks and different USB ports on my Dell XPS8700.

However, if I manually copy the files (using WIndows Explorer), the copy works fine. Also, if I format the memory stick as NTFS, I don't get a BSOD.

System is patched with all the latest patches/drivers (according to Windows update, Dell Update and SlimDrivers).

Any assistance/thoughts would be appreciated, as this only seems to happen with FFS.

[Zenju]

Probably a driver bug of the new OS:
https://msdn.microsoft.com/en-us/library/windows/hardware/ff557429%28v=vs.85%29.aspx

[philip_katz]

Thanks. I had seen that page, and the two soultions are to run chkdsk /f /r on the drive (which I have done, with no errors), or to add memory (I have 12Gb RAM, and wasn't running anything else, so nonpaged pool memory depletion is unlikely to be the issue).

Also, a driver bug wouldn't explain why I can copy the files using Windows Explorer with no issues - unless FFS is doing something "clever" in how it copies the files...

[Zenju]

BSODs are always driver bugs or (less likely) operating systems bugs, but never caused by client applications like FFS. Sorry, this is a MS issue.

http://blogs.msdn.com/b/oldnewthing/archive/2015/08/13/10634840.aspx

[philip_katz]

Understood, thanks, but is there a difference in the underlying mechanism by which FFS copies a file from my hard drive to my USB memory stick compared with me doing it manually in File Explorer? That might help me to identify the problematic driver.

Appreciate your help.

[Zenju]

> difference in the underlying mechanism

Fundamentally, no. Although Explorer and FreeFileSync don't use exactly the same Windows API (Explorer uses CopyFile2, FFS CopyFileEx), their underlying implementation (BaseCopyFileExW) is the same.

From the symptoms the BSOD could be caused by any driver that has influence on file system accesses. However practically speaking it's probably a non-Microsoft driver (Win 10 is new, so this wouldn't be surprising) or a virus scanner (I've seen BSODS caused by Avast drivers on Win 7).
The symptom that the BSOD occurs with FFS but not (yet) with Explorer may have to do with different file access patterns and stress on the file system (some driver bugs only occur during heavy load).

[Zenju]

More practically speaking: If you really want to find out what exactly went wrong during the BSOD rather than waste time guessing, you can try to debug the minidump file that Windows creates automatically in %SystemRoot%\MEMORY.DMP with WinDbg.
If you have some programming experience, simply opening this file (and clicking on "!analyze -v ") often shows already which dlls (and thereby which drivers) were involved.