Double-clicking .tib file results in error

System: Windows 8.1 Update 1 Pro x64
True Image Version: 2014 b6673

I used TI 2014b6673 to make to make a bootable USB drive to perform a backup. I backed the target system up (Win XP SP3 if it matters) to an external drive with the option to validate the backup. I then proceeded to attach this external drive to my Win 8.1 system and double-click the .tib file to pull a couple of files out of it. However, when I double-click the .tib file I get the following error:

Archive Open Error

An Error occurred while opening the backup archive.

Cannot continue the operation because the backup is corrupted, or it is being used by another process, or you do not have enough permissions to perform the operation.

Just to make sure I turned off my AV (ESET) to make sure it wasn't causing an issue, but this didn't help.

I then proceeded to launch TI 2014 and open the .tib and perform an archive validation which completes successfully.

I have performed the above three times, all with the same results.

Just prior to performing the above I had upgraded from TI 2013, so I tested a couple of TI 2013 .tib files and when I double-click them they open properly in Explorer.

So, any ideas?