I've been using this program for a few years with much success. After running it on an external disc where I found several images I want to look at that all have an excellent state I get error message that says "the device is not ready". What does that mean and how do I resolve the issue?
That generally means that the storage device has been powered down to save energy.
To prevent this from happening, please take the following steps to disable "Turn off hard disks" and to disable Sleep/Hibernation modes:
Click Start > Control Panel > Power Options (or, on newer versions of Windows, click Start > type Power Options > click 'Edit Power Plan' and move to step 3)
Next to your selected power plan, click "Change plan settings"
Click "Change advanced power settings"
Expand the Hard Disk section > Turn off hard disk after
Change the setting to Never
Expand the Sleep section > Sleep after
Change the setting to Never for "On Battery" and "Plugged in"
Expand the Allow hybrid sleep section
Change the setting to Off for "On Battery" and "Plugged in"
Expand the Hibernate after section
Change the setting to Never for "On Battery" and "Plugged in"
Expand USB Settings > USB selective suspend settings
Select "Disabled" from the drop-down
Click Apply > OK.
Once you have changed these settings, please scan the drive again to see if you continue to receive this error message.