Thanks cluberti. I thought I would test using DebugDiag on my own system first. I manually injected the leak tracking DLL into my explorer.exe process and let it run for a while. I then created a full dump, and ran the memory pressure analysis on it. I got an error in the report when it was trying to analyse the heap info. Where it shows the Heap Details, my first heap (default process heap) shows reserved memory of 0 bytes. The report then gets an overflow on trying to display the committed memory as a percentage of reserved memory, as reserved memory is 0 and divide by zero creates an overflow. Is this something you have seen before, or do I need to do something differently. My system doesn't have the issue of my client, but I wanted to get familiar with the tool before using it on his system. I noticed that DebugDiag v1.1 indicates it is only tested up to Windows Vista and prior. As I'm running Win7 (as is my client) is this going to be an issue? After a bit of searching, I have found that v1.2 is in beta, and can be requested from MS. I'll try this version if and when I can get it. I have attached the analysis report file. Memory_Report__explorer.exe__11102010111316802.rar