Migrate Shop to a new server, BO problem

[G.S]

Hello!

We have a small problem after moving from one server to another (v 1.7.5). Basically, we have performed the following steps:

https://www.prestashop.com/en/blog/how-to-migrate-prestashop-to-a-new-server

So far, everything is fine, but the backoffice page works only in debug mode, otherwise the page remains white.
In debug mode everything seems to be ok, except switching the template (e.g. back to classic template).

 

Compile Error: require_once (): Failed opening required:
require_once $ this-> disk-> get ('path'). DIRECTORY_SEPARATOR. $ this-> attributes-> get ('name'). 'Php';

The Prestashop log-files doesn't show any problems.

Does anyone have an idea where to find the problem?