I'm not sure if this is relevant, it may only apply to Windows NT, but a while ago, a colleague of mine was having difficulty tracing an apparent memory leak in a VC++ application. The application appeared to be slowly eating away at the available memory.

After much searching through code & documentation, we found hidden away in the documentation a section on the memory management garbage collection. This apparently only kicks in when the available memory reaches a critical point or when a request is made for more memory than is currently available. In the mean time, the memory reporting routines report less & less memory available. What the documentation suggested was having another application which simply requests a large amount of memory & then exits - this forces a tidy up of all free memory & the available memory reported is accurate. He wrote an appropriate app. to test & sure enough the apparent memory leak was resolved.

Unfortunately, I cannot remember where the article was, it was in the online documentation, rather than TechNet or KB article.