Microsoft's Software Licensing and Protection Services (SLPS) - Not for 64 bit

I am attending Microsoft's TechEd Developer conference in Barcelona this week (and having a great time).
One of the more interesting things (to me) that Microsoft is showcasing this year is a new product for ISVs called "Software Licensing and Protection Services" or "SLPS".
There has been 2 "breakout sessions" on SLPS, there are signs, flags, and posters advertising SLPS everywhere, and there are more "ask the experts" stands about SLPS than any other single topic here.

SLPS is a very interesting anti-cracking method involving a "unique virtual machine permutation" for each ISV or software title combined with a typical license activation server or service. For details see

It seemed like a great product for a small ISV like us, and so I spent some time digging into this subject here at TechEd.
Microsoft sells SLPS through various resellers including PreEmptive - who combines this with their DotFuscator product.
PreEmptive also has a stand at the TechEd, and they offer a "challenge" where they add SLPS (and obfuscation) to an existing .NET executable to demonstrate how all this works.

PreEmptive gave me a very nice walk-through using one of the .NET based .EXE modules from our upcoming Simple DNS Plus v. 5.0.
The protected / license wrapped version worked very nicely during the demo on PreEmptive's computer, and following the demo they e-mailed me a copy of this to try on my own computer.
Unfortunately it did not work as well when I downloaded the file to my laptop later that evening - basically it just crashed.

This morning I attended another session about SLPS by Aidan T. Hughes (Development Manager for SLPS at Microsoft), and later in the day got a chance to talk to him personally about this - and show him the application crashing on my laptop.
It turns out that SLPS only works with 32 bit processes!
Since my laptop runs 64 bit Vista, and the .NET application was originally compiled for "Any CPU", it runs as a 64 bit process.
This worked just fine before SLPS was added. But with SLPS it crashes because it cannot load the 32-bit-only SLPS DLLs into the 64 bit process.
Quoting Aidan: "We haven't gotten many requests for 64 bit support, so this is not something we have tested a lot..."
Unfortunately he didn't give me much hope that this would be fixed in the near future - "we will look into this for future versions...".
His only suggestion was to re-compile the application for 32 bit (x86 CPUs).

Unfortunately that is a showstopper for us.
Many of our users have been asking about 64 bit for some time now.
All new CPUs from Intel and AMD are 64 bit capable (both companies have stands at TechEd and I checked with them both) and Microsoft's own flagship product Window Vista comes with both 32 and 64 bit versions in the same box.
So I am surprised that Microsoft would launch this new product without 64 bit support.

That said, I would like to thank the staff at PreEmptive and Microsoft's SLPS group here at TechEd for their great help and personal attention to this.

Jesper Høy's
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