Opened 16 years ago

Last modified 16 years ago

#3370 closed Bug report

heap corruption killing explorer.exe

Reported by: evelator Owned by:
Priority: normal Component: Other
Keywords: Cc: evelator, Tim Kosse
Component version: Operating system type:
Operating system version:


Running version under Vista SP1 causes explorer to crash due to corrupted heap. Had a Vista expert search through the crash log and they fingered the Filezilla shell extension as the culprit. Removed Filezilla and sure enough, explorer.exe is now a happy camper.

Read the past bug reports but did not see anything to indicate this is a known or fixed problem so I thought I'd let you know.

expert's report below. Bottom line is that this version of filezilla is not healthy.

HRESULT DUIXmlParser::GetSheet(LPCWSTR pszResID, out Value ppValueOut)


Check to see if its in our sheet list
for (UINT iSheet = 0; iSheet < _pdaSheetList->GetSize(); iSheet++)



return hr;


_pdaSheetList is a pointer, but its value seems to be 0x00000008 (or at least that was the address where the access violation occurred). Since it is a member variable and should always be valid, this suggests heap corruption. Given that the crashes happened in multiple files every few minutes, I would assume that some code loaded into explorer.exe is corrupting large amounts of the heap randomly.

There were 159 modules loaded into the explorer process when it crashed. Of these, my bet would be on fzshellext.dll (C:\Program Files\FileZilla Client\fzshellext.dll). It’s the newest library (compiled on 11/27/2007) other than SP1 files. It is hosted at From what I could tell, the version that you have on your computer ( has had numerous reported bugs related to its shell extension. And when I tried to install it on my computer, I started having issues with explorer.exe (not the same issues as you, but explorer kept maxing out the CPU, even after I tried to uninstall FileZilla).

Change History (2)

comment:1 by Tim Kosse, 16 years ago

Are you using a 32bit or 64bit Vista?

You mentioned Vista SP1 (which afaik is still in beta), can you still observe this problem if you don't install SP1?

If you create the registry key "HKLM/Software/FileZilla 3/fzshellext" and set the DWORD "Enable" to 0 and reboot, does the problem persist?

comment:2 by sf-robot, 16 years ago

This Tracker item was closed automatically by the system. It was
previously set to a Pending status, and the original submitter
did not respond within 14 days (the time period specified by
the administrator of this Tracker).

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