Hi,
I know I'm not the only one having this error, and I've read the other posts, but none contain any answer to solve my problem, so here is what happens :

I created a backup of my db, then erased the zp-core and old theme directory. I then uploaded the new ZP, and tried to access the zp-core/setup.php file. But I had a "500 Internal Server Error"
I read a post where it says it might come from file permissions, so I open my ftp manager, and change the WHOLE site to 755 (to be sure
Then I try running zp-core/setup.php, and this time, the setup page shows. But as soon as I click on the "Go" button, the same error occurs ! And if I try to go back to the setup page, it doesn't work anymore.
So I get back to my ftp and noticed that all the php files of the zp-core directory are back to 644 permissions ...

So, first, sorry for the big story. Then : how should I do ? Each time I set the correct permissions, the setup reverse them to ones that don't work ... any solution ?

Did you try 777 as well. Some host seem not to allow 755 for whatever reason.

Hi,
I just tried setting permissions to 777 but I have the 500 error. I've read that some hosts don't like 777 permissions for quite obvious security reasons.
But I'm pretty sure 755 is fine. As I described in my previous post, when I set permissions to 755, the setup displays. It's when I try to run it that it doesn't work anymore. And if I don't run the setup, my permissions are not touched.
It really seems to me that it's the setup script that is changing the permissions. But as I don't know how it works, I can't really check, or find a solution

Setup tries to set the permissions to what it needs. If it does not succed it actually tells that. Internal server errors often are related to modrewrite/htaccess. Did you check that?

I re-tried, this time without any .htaccess in my root directory, but the same problem occurs : setup shows, go, 500 errors, persmissions changed and setup shows a 500 error until I re-set permissions to 755

I just edited my zp-config.php file, and notice a "define('CHMOD_VALUE', 0777);" in it ... I changed it to 755 and the update did work, and my gallery is now up and running without any problem ...

What I don't understand is why did it work with my previous ZP install (1.2.6 if I remember well) But anyways, it works now and I'm happy. I just have a little modification to make to my share plugin since the getImageEXIFData() function doesn't seem to exist anymore

Thanks for your wonderfull work on ZP and the help !
Regards

Glad it works now. Probably sbillard will hav an idea about this.

getImageEXIFData() is deprecated and available if you enable the plugin for the deprecated functions. But best to update of course.