Multisite Installation

Hi there.
Due multilangual request i decided to activate multisite feature on my wp installation.
I added the code define(‘WP_ALLOW_MULTISITE’, true in my WP-CONFIG and “unlocked” the Nework feature under Tools.
But Wp is telling me I have to deactivate all plugins first. I did that, no active plugins running. The message still stops me from continuing.
I re-logged in already, still stuck with this.
Pleas help-Thank you!

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