It was reported elsewhere that the problem is that the default Crypto Provider is different for Windows 2000 and XP. It is Microsoft Base Cryptographic Provider (Rsabase.dll) for Windows 2000 and Microsoft Enhanced Cryptographic Provider (Rsaenh.dll) for Windows XP.
To fix it, try to set 'cprovidername' property of the _cryptapi class to "Microsoft Base Cryptographic Provider v1.0" which is value of dsMS_DEF_PROV_A constant in the wincrypt.h include file.

>Hi
>
>I am using encryption in my application. However it appears that encryption works differently depending on the version of Windows. I encrypted some information on my Windws XP workstation but was unable to decrypt it on my Windows 2000 workstation and vice versa. If I encrypt data on a Windows 2000 machine and then install my software on another Window 2000 machine the decryption works just fine.
>
>I am using the same password to encrypt the data on both machines yet the results are different using the same encryption class. I am using the crypto api from VFP 6 Foundation classes.
>
>Does anyone know what might cause this problem?
>
>Thanks
>Simon