PHP Fatal error: after update to 4.6

Unless you have a backup that you can restore from, downgrading is a dangerous process, which is why backing up before upgrading is strongly recommended both in the upgrade instructions and automatic upgrade interface.

It would be better to solve your current problem.

Try manually resetting your plugins (no Dashboard access required). If that resolves the issue, reactivate each one individually until you find the cause.

If that does not resolve the issue, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel, navigate to /wp-content/themes/ and rename the directory of your currently active theme. This will force the default theme to activate and hopefully rule-out a theme-specific issue (theme functions can interfere like plugins).

I have tried resetting plugins but this does not solve the issue.
After renaming the plugins directory, the same error is still there when trying to access /wp-admin/plugins.php

There’s a while second part there about the theme.

And, if that doesn’t work for you, please open your own thread: https://www.ads-software.com/support/forum/how-to-and-troubleshooting#postform

Hi James, I have tried the theme change as well, I am having the same issue “PHP Fatal error: Call to undefined function wp_convert_hr_to_bytes() in /home/”siteuser”/public_html/wp-includes/default-constants.php on line 32”

Why would I need to open a new thread?

Hello CMBrandon,

Any luck. I have experienced exactly the same issue today?

I connected to my site via FTP, I had a 4.5 offline version of WordPress available and uploaded the whole 4.5 version wp-admin folder to the site. Overwrite the server files and then your site should be up again and you should be able to get into the admin.

If you need a quick and easy way to develop WordPress sites offline, try this https://www.instantwp.com/

Thanks CMBrandon. I did exactly the same.. All good..cheers. Hmm still not sure what in the update broke it.. Plugin conflict I guess..

Thanks for sharing your solution!

Obviously a problem with 4.6 then since no suggestions on a fix have been put forward – rolling back to a version that worked is the only solution.

I take it then that you’re choosing to ignore all of the suggestions posted in this thread?

Have tried them – the problem remains so please do NOT mark this topic as resolved as it is far from it.

I have sine done an offline update to version 4.6 and all seems to have gone well.

It’s much nicer when you say what you’ve tried, so we know what to suggest next.

Try downloading WordPress again, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel, and delete then replace your copies of everything except the wp-config.php file and the /wp-content/ directory with fresh copies from the download. This will effectively replace all of your core files without damaging your content and settings.

Some uploaders tend to be unreliable when overwriting files, so don’t forget to delete the original files before replacing them.

Have tried a full reinstall of 4.6, have disabled all plugins.

The only thing that worked for me is going back to a 4.5.x backup. These “upgrades” cause more problems than they fix.

Well, if you’re staying on 4.5.3, then there isn’t much we can do to troubleshoot or track down the problem you had. Maybe 4.6.1 will be better for you when it comes out.