Does the update also works for deactivated plugin?

Interesting… let me do some testing and get back to you.

Just tested this on a localhost install running PHP 7 and WordPress 4.5 RC1. It works alright for me. Have you tried using the “Force Updates” button in the Advanced tab in Easy Updates Manager? Push it and wait 90 seconds, then refresh the page and see if the plugin updated.

Also, I assume you have the Automatic Plugin Updates setting set to either Enabled, or Select Individually (then you would need to select the plugins that you want automatically updated).

We are using the Plugin within a multisite installation with the latest
WordPress version. Does the Plugin work with this kind of installation?

Yes. In fact it was designed to work with multisite first when we released 5.0

Just double-checked a MS installation with two outdated non-network enabled plugins. Updated those just fine.

Are the deactivated ones third-party (not hosted on www.remarpro.com)? We’ve had problems with those in the past as each one seems to have their own update mechanism.

@duttlinger
Any update? Were you able to figure it out?

I am resolving this for lack of response from the OP.