Can't Access WP Admin CP After Update

seems as if it did not update properly try replacing all files and folders except wp-content folder and wp-config.php file

Same here. Updated some plugins and now can’t login…. I get website cannot display the page. Website is under maintenance or has a programming error. What’s the deal? Don’t know how to fix it if I can’t login to the wp-admin sectiion.

Tried that and got this instead:

Call to undefined function is_multisite() in /hermes/bosweb/web124/b1240/ipg.astralplanestudiosc/blog/wp-includes/wp-db.php on line 505

@zepher If you have maintenance page then you will need delete .maintenance file which is hidden file using ftp
you will need deactivate all plugin
if you have access to your admin panel, try deactivating all plugins. If you don’t have access to your admin panel, try manually resetting your plugins, using ftp rename plugins folder to plugins_hold and create a blank plugins folder If that resolves the issue, delete blank plugins folder and rename original back to plugins reactivate each plugin individually until you find the cause.

I deactivated all plugins before I attempted the update. So basically now, just create a blank folder and try again?

Thanks @govpatel, I ended up creating a blank folder and renaming the plugins to a new name, got the wp-admin section working again. Then I placed in the new folder all the plugins that had an earlier date than the ones that were updated, and it worked fine too. Then I placed the plugins that were updated right before the error and it glitched out again. Then I placed them in one by one and found the one causing the error. Thanks for the help.

You are welcome 90% of time its plugin and themes conflict that causes the problem