With PV Elite 2015 a new file extension was introduced to combine both output reports and the input file into a singular new format with the extension *.pv.  For users that currently have PV Elite 2014, when opening this file in 2015 the format would change and PV Elite 2014 would no longer open the file.  

In order to convert the *.pv extension back to the PV Elite 2014 *.pvdb file, perform the following: 

1. Open up PV Elite 2015 and go to your configuration settings.

2. Under "default value settings" make sure "Do Not Compress the Input Files" is checked.  Now your PV Elite 2015 files will retain the *.pvdb extension to be backwards compatible with PV Elite 2014.