[ndoktoruser]

Hello all,

I have vbulletin 5.2.0 installed and running.
I am trying to upgrade it to 5.2.3.

Before someone asks me "why not 5.2.5?", I will upgrade it to 5.2.3 first, because of my php version. In a later moment, I will upgrade it to 5.2.5.

So, back to the problem...
Whenever I switch the source code to the version 5.2.3, I receive some 404 errors. For example, the CSS is not found nor login.php. (image attached number 1)

State of forum after upgrade:
- start page is shown, but CSS is broken (error 404 to css.php) and login is not shown (error 404 to login.php);
- subforums and threads are not shown (!);
- admincp (image attached number 2) login page has a new link (from admincp to core/admincp), but it doesn't login after I submit username and password (404 to login).


Interesting facts

1)
When I upgraded from 4.2.2 to 5.2.0, my upgrade link was http://my.forum/install/upgrade.php.
To upgrade from 5.2.0 to 5.2.3, my upgrade link is http://my.forum/core/install/upgrade.php.

2)
Even though I had a different upgrade link, I successfully upgraded the forum to 5.2.3.
By successfully, I mean that no errors were displayed during the upgrade process.

3)
Admincp was http://my.forum/admincp, now it is http://my.forum/core/admincp.

4)
Once the forum was upgraded, the start page (http://my.forum) is loaded, but with a lot 404s, which can be seen in the picture 1 attached:
- http://my.forum/css.php
- http://my.forum/auth/login-form
- http://my.forum/ajax/api/options/fetchValues
- http://my.forum/ajax/api/phrase/fetch



What have I tried to do

I tried to change the values:
- v1: table datastore, column title like "options" and "publicoptions", value like "frontendurl" => "my.forum" to "my.forum/core"
- v2: table datastore, column title like "options" and "publicoptions", value like "frontendurl_login" => "my.forum" to "my.forum/core"
- v3: table setting, with column varname like "frontendurl", value from "http://my.forum" to "http://my.forum/core"
- v4: table setting, with column varname like "frontendurl_login", value from "http://my.forum" to "http://my.forum/core"
- v5: file core/includes/config.php, variable $config['Misc']['baseurl'] (line 122), I set 'http://my.forum/core'

The change in the values v1 and v3 made some CSS in the start page to work (status 304), but broke the images (404).
This same change in the values v1 and v3 broke CSS in admincp, but I successfully login. All the CSS in the admincp is broken (404).

The other changes made no effect.