Need to move email database

I have an emclient installation  on a hard drive that has been removed from my system.  While it is still readable, the drive is not bootable, so, the application cannot be run from this drive, i.e. the “old drive”. 

I have installed emClient on the replacement drive (i.e. the “new drive”) but of course, it does not have access to the old drive’s database, as “old drive” is no longer installed.

So, I need to some move the “old” emClient database so that the “new drive” installation can access it.  However, I do not have a backup on “old drive”, and, since it cannot be run on that drive, I cannot do a backup.  And, it appears that just moving the Roaming directory may not work, based on another posted message.

The possibilities that seem to be feasible are:
1.  Copy the Roaming directory from the old hard drive and replace the Roaming directory on the new hard drive, so that EMClient finds that. 
2.  Copy the Roaming directory from the “old drive” to a new location on the computer, and then point emClient to that new location, possibly just using it there, or, doing a backup and moving it (?)
3.  I could hook up the old hard drive temporarily as an external hard drive and then have EMClient redirected to point to the resulting folder on the old (external) drive.  If that works, then I guess I could do a backup of that data and then move it.  This seems equivalent of #2, except if only that directory is moved, then the note below would not apply.

Note that I would need to be able to avoid attaching the old hard drive (now external) until the machine is booted already because that was the cause of the whole problem in the first place–the previous Windows installation would be found but not boot.  (Don’t think it’s important for this, so no details offered) 

Are any of these options possible? 

Hello Dave,
the first option should work just fine.Just copy instead of moving it, so in case it does not work, you can try the option with the back up.