Thanks for the info. This is for a vertical app that is installed on multiple OSes, so I'm going to stay away from the Crypto API if possible. Do you know of any components that use the same RSA encryption but are OS independent?

>>>>Also, will it provide 128-bit (or higher) encryption for all OSes Win95 and up? It appears to use the "RSA Full" provider, whatever that is <g>.
>>>
>>>It will not natively do that as there was a change in export law restrictions so it went from 40-bit (at the time of Win95) to 128-bit now. You have to change the settings to use rsaenh.dll (RSA Enhanced).
>>>
>>
>>Well, that stinks <g>. It looks like the best way to make sure 128-bit encryption exists on the machine is to install the latest version of IE (a challenge for Win95). Do you know if this will cause 128-bit to be used by the FFC class, or will more work be required?.
>
>More is required. Look at the wiki link I mentioned. There are checks you can do in the registry to see that rsaenh.dll is installed:
>

>Run regedt32.exe and look for
>HKEY_LOCALMACHINE\
>SOFTWARE\
>MICROSOFT\
>CRYPTOGRAPHY\
>DEFAULTS\
>PROVIDER\
>Microsoft Base Cryptographic Provider v1.0
>
>Must be set to something like:
>C:\WINDOWS\System32\rsaenh.dll
>

>You have to change you copy of Wincrypt.h to point to rsaenh.dll or change the one pointed to BASIC Crypto Provider to point to rsaenh.dll instead. And even then you must test that the copy encrypted in one OS iss able to be decrypted in other OS version as there are different versions of rsaenh.dll (PITA)
>

>#DEFINE dsMS_DEF_PROV_A       "Microsoft Base Cryptographic Provider v1.0"
>

>Look at the very end of this article for availability:
>http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnsecure/html/intcapicom.asp
>
>Here's a DLL version search page from MS:
>http://support.microsoft.com/dllhelp/default.aspx?dlltype=file&l=55α=rsaenh.dll&S=1&x=7&y=10
>
>HTH