#3 move the file pointer

[FireFox]

After using extcv when I try to mount the volume I get the message "Error: The process of encryption of the partition/volume has not been completed. It must be completed first". When trying to complete an encryption using truecrypt's resume interrupted process under the volumes menu I get this error: "An attempt was made to move the file pointer before the beginning of the file". If I try using extcv again it says "An error occurred when attempting to mount volume". Is there any hope for recovering the 600+GB of data?