Can plugin still work if deactivated

Hi,

Apologies but it may be nothing to do with your plugin but we don’t know where the problem is so exploring all avenues. We used the plugin on our site but deactivated it several months ago. It wasn’t deleted from the plugins page though.

Yesterday I updated the website, Divi Theme and all other plugins and it was working fine. This morning the homepage is working fine, the curriculum menu and subpages are working fine (sub domain) but all other main pages are going to the 404 page.

I’ve seen this with other plugins where even when it is deactivated or even deleted it somehow retains some settings. Is this possible with this plugin?

Many thanks

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