Shows as succesfully copied but index.php blank

I have used this plugin a few times without issue, it’s a great script. Today however it has taken three attempts creating the package to make a zip that would not be rejected by installer.

This one does not get rejected but when it gets to the end the index.php is just showing a blank page. I can’t get to admin or anything yet all files appear to be in place when looking at folder through ftp client.

It has been duplicated on the same host (different temporary domain)so I can work on this site whilst the main one remains live (editing template files/ css etc) and then I will copy those relevant files back to live site.

Installer shows no errors in report and gave no warnings when creating the package.

Any ideas ?

Thanks

https://www.ads-software.com/plugins/duplicator/