Unable to create output file error

I have inherited a drupal site and am trying to debug some issues. I am fairly new to drupal.

I have copied the site to a different server to use as a test environment.
The site seems to be working fine except that when I try to output a pre-existing 'repor' as pdf get the the following error

TCPDF ERROR: Unable to create output file: /home2/freelond/public_html/sites/all/pdf/historic_report/agilityweb-2013-09-18-1246.pdf

The location referred to is the original server and not the new one (hence the error)
I cant see where to set the path for the output file.

The site settings have all been changed (as far as I am aware) in Configuration and I can see any setting specific to this module for this (but may not be seeing wood for the trees!)

I have also cleared caches.

Can anyone suggest anything here?