Error in opening an encrypted email in lotus notes 7

[magicbawa]

I used to receive the encrypted mail. I was having the public key of the sender and private key of mine imported in my lotus notes. The private key expired and I renewed it. I have informed my sender also. He is sending the mails with my new public key. After that i am not able to open the emails from that sender. The lotus notes application is closing automatically when I open that mail.

Can anybody tell me why this is happening and what is the solution for this?

Thanks a lot.