Upgrading Fatal Error

[dmgerrard]

I am trying to upgrade this gallery http://www.rfaaplymouth.org/THgallery/index.php from 1.4.27 to 1.5.6 but repeatedly get this error -
Fatal error: Call to undefined function: check_rebuild_tree() in /var/www/vhosts/rfaaplymouth.org/httpdocs/THgallery/update.php on line 693

Please advise. I think I have enabled debugging via the database.
(This gallery is a copy of the live one at http://www.rfaaplymouth.org/talhandaq/coppermine/index.php  so I havn't lost anything yet.)

[phill104]

Did you delete all the files except include.config.inc.php and your albums folder first? If not give that a go then upload all the 1.5.6 files before running update.php

[dmgerrard]

Many thanks, that has worked. I previously only overwrote the files. Does the documentation need to make it clearer that they should be deleted?

[phill104]

It is not all instances that do. Sometimes files get left over from mods etc, sometimes write permissions on the odd file get changed on the server and  your ftp app doesn't replace them. In my mind it is always good to do a cleanup this way.

Thanks for resolving your thread.