Trying to upgrade timeslips2012 to 2015, but shortly after the installation begins I get an error...

Feature: Sage Timeslips Application and Help Files

Component:

File:

Error: Catastrophic failure

The computer is running Windows Vista.  I've tried rebooting to remove any remnants of 2012 still in memory.  I've tried running the installer as admin.  All no good.  I would try installing it on another computer, as they have XP, Vista, and 7 mixed environment, but I am concerned that it still won't install on this PC, leaving this user unable to work in timeslips.  Please advise to how I can fix this issue?