Error while upgrade forum


My current forum version is 2.15. I have download the full PHP version of 2018.4.11. However, I got the error message “An error occurred trying to update the database
Table ‘phpbb_admin_nav_module’ already exists” while trying to install the PHP new version.

Here are the steps that I did:

  1. backup my database.
  2. backup the whole old forum.
  3. delete the old forum files on my server.
  4. copy the newer version into my server.
  5. change mod for .config file.
  6. run
  7. fill in the old database info.
    —> give me the error “An error occurred trying to update the database. Table ‘phpbb_admin_nav_module’ already exists”

However, If I try to connect to a new database, the installation is fine, but it will give me error “can’t recognize one field in php-categories table.” in the restore database step.

Please help.



It’s complaining, becuase it’s expecting an empty database, not one allready full of stuff.

I’m assuming that you want to upgrade phbb? And you want to carry over all of your old posts into the newer version? In that case you’ll want to restore your old files so that your forum is in a working state (old version). Next go to the phpbb website, and download the upgrade version and follow upgrade instructions.

Alternativly, I suppose you could clear out the database entirley, get the new install of phpbb working, and then import your entires back through my database restore - but that won’t bring back the layout you were using - just entires and settings. The upgrade would really be better.


You should just run the upgrade


Yes, I really want to upgrade to PHP new version and keep the old posts. I will try the upgrade way. at PHP site, there are three available file to download. which one is suitable for my case?

One question. Can I use the one “full mod PHP” new version or I have to use to standard one from PHP site?

thanks Matttail

Hi Shad, thanks. when should I run the update_to_latest.php

right after installation successfull? before deleting the install folder right?


what forum software are you trying to upgrade, phpbb -yes?


Yes, the phpbb forum.

One thing I see is the new version 2028-4-11 fully mod phpbb forum doen’t have the contrib folder.

check out this Tutorial
and find the part that says “If you have no MODs installed” in yellow (assuming that’s the case) Just follow those instructions. (please not this assums that the old forum is intact and running - so you’ll want to make sure that you’ve put all the old forum files back)



I got it working. However, I didn’t see any changes yet. I will read to see what does the upgraded version include?

Thank You Very Much for your help.


looks like it’s mostly behind the scenes stuff. the actual changelog gives a detalied list. You might find a new feature or two hidden away some where, but there’s not going to be a change in the look and feal really.


what i ususally do is create a new db, install a fresh copy of the forum, make sure it is up and working.

then drop all the tables through phpmyadmin, then run a import command through a ssh session.
it will then create all the tables again for you from your backup db.sql file. that should work fine.
also , from what i read on other sites there is a function in the admin panel of phpbb to import a old db file