Thank you for asking this question in the support community. To upload the .spd file you have downloaded from the ADTRAN unit to the NetVanta VPN client, you can navigate to to following: Configuration---->Profiles---->Add/Import. From there you will be able to upload the VPN client configuration. Please, keep in mind that you may need to re-enter the VPN preshared key on the client. To do this, go to the profile and click edit, then identities, and then from there you can enter the VPN preshared key on the client. I hope that makes sense, but please do not hesitate to reply to this post with any additional questions or information. I will be happy to help in any way I can.
Thanks Levi. What threw me was that I was led to believe based on the menu choices that you could only import an *.ini file. The import worked perfect after I selected *.*.