strange... we get the results attached
The .zip file contains a R5 and a R9 .max file. If you open these in 3ds Max and go to File > File Properties..., Custom tab, you should see a custom property called "test", with value "Hello World".
The two .png files are from Windows XP and Windows Vista, for a right-click > Properties > etc. from Windows Explorer for the R9 .max file. As you can see, not quite "Hello World". The same procedure on the R5 .max file does give proper results.
Sadly, parsing code we had to parse file properties that worked for 3ds Max 5 gave us the same garbled mess, rendering it useless on r7-9 files (not sure about 6).
32_FjBgI4EB8LYxhFt1hmQ6.zip