Fatal error: Call to undefined function self_admin_url()

while updating a wordpress site, saw the subject error….

Seems like this happened because the recovered password wasn’t changed. That generated a warning which I suppose led to the fatal error during the upgrade process. So everything was fine, but note to self: change the recovered password before upgrading.

Now updating another custom wordpress site’s plugins, for how long will I see this?
“Briefly unavailable for scheduled maintenance. Check back in a minute.”
removed the “.maintenance” file in the top level folder and that got us back on track.

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another one… someone deleted the admin account. inserted user ID 1 and let’s see if it works… nope did not work, also need to look at wp_usermeta table – found that user 2 has the admin permissions!