Open encrypted container on different installation

For reasons of company policy, I no longer have a licensed copy of SEE. I do, however, still have an encrypted container which I need to open to extract the files inside.

I had hoped it was just a matter of transferring the .pgd file to another installation and opening with the correct passphrase - however, I get an "incorrect password" error.

Is it perhaps necessary to have my secret key installed in order to open the container? Or is there some other reason why this is failing?

All info gratefully received.

MT