Oops! That page can’t be found.

Try deactivating all plugins. If that resolves the issue, reactivate each one individually until you find the cause.

If that does not resolve the issue, try switching to the Twenty Sixteen theme to rule-out a theme-specific issue (theme functions can interfere like plugins).

Deactivate all yet same problem occurs, i.e can’t edit, it still show the same message.. but i realize this only happen on page.. my post/shop product are all okay..

but i can add in new page and edit/update with no problem. Worst case, i may create a new page and remove the page that doesn’t work..

Will try to switch to theme and see how it goes ..

thanks for everything

If it’s no different under the Twenty Sixteen theme, 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 on the server 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.

Sorry guys for my late reply. indeed all is well, it is modsecurity problem.. i can edit and update after turning off… but i suspect is server issue..as after i turning on after update.. i can still edit and update next day.. may be just my luck to update when there is “problem”

Anyway, all goes well now, thanks for everything ..

mod_security has a series of rules, so it sounds like one of them is just a bit overzealous.

Contact your hosting provider about it with some exact dates/times you encounter the block (in other words, trigger it again with mod_security on so you have the date/time), and they should be able to track down the conflicting rule and disable it.