I wish to update my site from 1.27, to the latest version.

I have followed the correct procedures for template over rides etc.

I have backed up the database, and copied the site to my local server. Installed database on local server.

Unpacked, and copied V1.36 to local server, usual "windows" warning "files etc with same name will be overwritten". Click ok.

Open localhost/cart, and am greeted by insallation program
Unfortunately, a little further into the process, I am informed I am not in "upgrade" mode.

I delete contents of shop folder, and place a new copy of existing shop in folder.
This time using filezilla to 127.0.0.1/cart I FTP v1.36, using overwrite if exists.

I experience the same problem.

I delete contents of shop folder, and place a new copy of existing shop in folder.
This time using filezilla to 127.0.0.1/cart I FTP v1.36, using overwrite if newer.

Once again, same problem

Obviously I am misunderstanding the procedure .

I have looked at various threads, and succeeded in confusing myself.

Would some kind soul point me at an Idiots Walkthrough please.