Download this:
http://forum.avsim.net/files/go/4e220b78834210be0ef631a300bbf7ce/avsim-crash-to-desktop-guide-for-fsx-p3d-fs9If you can't access this document, post back and I will send it to you.
Here's the section of the doc that deals with ntdll.dll crashes.
BTW I used to get this in FSXDX9 very frequently. After switching over to FSXDX10 I've never had it again. Coincidence? Cured it for me!
NTDLL.dll – Several possibilities as follows:
Heap metadata can become corrupted and it has been identified by Microsoft as one of the
most common causes of application failures. When an application crash shows the faulting
module as ntdll.dll along with the Memory Access Violation (0xc0000005), then Windows
places the application on a watch list and, if the application crashes at least four times or
more in an hour, the fault tolerant heap service will configure the application to use the
fault tolerant heap service in the future (Source - Chapter 10, Memory Management,
Windows Internals, Part 2: Covering Windows Server 2008 R2 and Windows 7 by Mark E.
Russinovich, David A Solomon, and Alex Ionescu). The service is part of the Security
Center service so you need to make sure this service is turned on.Copyright 2013 – AVSIM Online – All Rights Reserved
You might get an NTDLL.dll shown as the faulting module if you have MyTrafficX 5.4c
installed. It is believed to be caused by an AI scheduling programming error. A fix was
being worked on.
An NTDLL.dll crash can also occur if your system overheats or you have wrong voltages set
for your installed RAM or CPU but this is less likely as you will most likely get a BSOD
instead of a CTD.
Removing the UIAutomationcore.dll from the main FSX folder will also fix NTDLL.dll
CTD’s for many.
Check your dll.xml for duplicate entries or any corruption. Some have fixed the NTDLL.dll
CTD by removing duplicate entries and/or old software entries where the software is no
longer on your system.
Good luck! These things a a major headache and suck to diagnose.
Steve
Addendum:
Check out this forum. You'll have to register to get on Avsim's forums.
http://forum.avsim.net/forum/262-crash-to-desktop-ctd-forum/?sort_key=views&sort_by=Z-A