Lettre recommandée avec accusé de réception valant mise en demeure

[staglussan2]

Hi there, I'm having trouble translating this sub-heading for a legal document regarding illegal content on the internet. the sentence is:

Lettre recommandée avec accusé de réception valant mise en demeure.

and my poor attempt:

Registered letter of formal notice for unlawful content??

I know I have changed the sense slightly and missed out some bits but I am struggling to understand the sense of "accusé de réception valant"...

Any help would be much appreciated, thank you!

 

[Ellea1]

Hi

Registered letter (with confirmation of receipt) is worth (serves as) a formal notice

something like that

La lettre = mise en demeure pas l'accusé de réception.