Omeka has encountered an error

I upgraded to the latest version of Omeka and now I get this error message when I go to http://xx.xx.xxx.xxx/omeka/admin/
When I go to http://xx.xx.xxx.xxx/omeka/admin/users I get this message:
Not Found
The requested URL /omeka/admin/users was not found on this server.

Can someone help me out?

Thanks

The error I get is "Omeka has encountered an error". I am not sure how to deal with this

Have you tried out the instructions for retrieving error messages on the codex? That's usually the first step when you get an "Omeka has encountered an error" page.

yes, but I don't have the .htaccess file in the root of my Omeka installation, so I couldn't do it.

That likely explains it. Probably when you copied the new files to the server, the .htaccess file was missed (some FTP clients skip 'hidden' dot-files). Double check that, and see what happens.

i had this issue, too when first starting out. If you're using FileZilla; you'll need to allow transfer of 'hidden' dot-files by:
Preferences>transfers>file types>check-mark 'treat dotfiles as ASC11 files'
Also, if you're using a shared server like Bluehost (in my case)- the hidden dot files will not be visible in the File Manager (on the C-Panel); you'll have to go into the Legacy File Manager to view and edit the file

thanks. Yes, I'm using filezilla but I already had "treat dotfiles as ASCII files" checked.
I am curious why I am missing .htaccess file even when I just look at the new downloaded Omeka folder on my local computer.

Check the settings for viewing files -- the viewing and transferring might be different settings

OK, got the .htaccess file and was able to retrieve the error. It is:
"Omeka Configuration Error

Your Omeka database configuration file has not been set up properly. Please edit the configuration and reload this page.

So then I copied the db.ini from my previous Omeka installation. That fixed the error message. It told me that my database had to be upgraded. But now I'm unable to login.
How do I fix this?

nevermind I'm in