>Thanks Thomas. I tried to google this and did find a lot of patch exes, is that all there is to it?

Yes. But I personally would prefer either a patch program from a source I trust with my money as well
or a program where I can read the source and compile/run in interpreter myself.
You change an Exe - which is what most virus programmers are after. So at least verify afterwards ;-)

>But also learned that this is not much help, if at all, on 32bit OSs but should help in 64bit OSs. Is there something that can be used to check if this app is really benefiting with the patch on either OS?

Best is to compare your special use case.
I am pretty certain that a graphic[-heavy] program working on large pictures will
benefit if the pic fits into leftover free ram in 3GB but not in 2GB.

A DB program reexamining the same data set will have benefits if the analogy is sound on data set size.
If the memory is not needed, chances are that you will see either no difference or performance drop.

Measure programmatically so you don't fall prey to placebo effects -
there might be internal maximum borders barring the use of that last GB even
if largeadressawre is set. As Vfp was one of the fisrt programs moving into 32 bit space such barriers
were probably more prudent back then and in C/C++ for sure more necessary than in C#/Java.

Going on a limb: if you are not tracking memory usage with WINAPI now, chances are that benefits
will be minor compared to small changes in your program. And giving 50% more memory, unless
data sizes wiill remain constant [seldom true...] will offer only a short time before other measures are needed.
If you are after WS /personal speedup, get more physical RAM and bet on disk caching with 64bit OS
or use 32-bit OS supporting PAE if for some reason you need 32-bit. Or get a SSD.
Or at least many discs, using round-robin-schemas in coding IO-heavy steps.

If you have lots of clients with speed problems, get them to pay for making the app faster: that scales
usually pretty good after 20 machines, if you not only compare RAM cost but install time as well.

regards

thomas