I'm on Windows 7, latest versions of WLM and plus. When I try to set the encryption, I get this error upon hitting apply.

Make sure you have all the Windows updates and fixes.
If you still recieve the message after a reboot, set the keysize to something else.

If windows XP was able to handle keys that were for the highest encryption keysize, you'd think Windows 7 should be able to handle the same level with ease.

All updates seem to be installed. Unless there is one I can/have to install manually. I get the error for all keysizes.

CookieRevised's reply to Logs encryption problem

To try and fix the error "Sorry, the cryptographic key could not be generated on this computer.":

First set a lower key size for generating the encryption in the Plus! preferences to see and test if the following resolutions help. Not an option. If I had maximum size with windows XP, I shouldn't have to settle for anything less with a computer 5 times better than my XP machine. Besides, I've already tried lower settings. The only keysize that works it to have none at all, and no encryption isn't an option.

1) Make sure you have the latest version of Messenger Plus!. As I said in my original post; WLM and Plus! are completely up to date.

2) make sure you have all the latest Windows updates and fixes. This is highly important. As I said in my first post; Windows 7 is also completely up to date

3) You also might wanna look at all the resolutions described in this MS KB article: http://support.microsoft.com/kb/822798. Try them all one by one! The problem isn't that one of the updates won't install. My machine is completely up to date.

4) Try to (re)install the Cryptographic API redistributable. Tried this. didn't work.