Best way to track down a memory leak (C#) only visible on one customer's box

Question

What is the best way to track down a memory leak that is only found on one customer\'s test/release box, and no where else?

Answer 1

PerfMon can be helpful (http://dotnetdebug.net/2005/06/30/perfmon-your-debugging-buddy/). There are several counters that may help narrow down what resource is leaking, and at what rate, etc.