Einar CF 1.1 didn't had any crypto classes but CF2.0 has it, not all of them but most of them.
I use the Rijndael class in my applications and it works great in WM5 and CF2.
so what class are you trying to use?
Also you sure in your project you are pointing to the CF2.0 assemblies, or still using the 1.1 assemblies.

>The compact framework does not contain (hardly) any crypto stuff (System.Security.Cryptography). I have been using a class I wrote to encrypt and decrypt text (which used a lot of stuff from System.Security.Cryptography). Now I need to share my encrypting and decrypting with a PPC application and since a lot of this is not available in the compact framework I either have to write my own or use someone elses.
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>Has anyone in here done some crypto stuff in the compact framework? Any relevant information would be greatly appreciated.
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>Thanks,
>Einar