Cannot receive meeting

Hi,

I've a very stange thing on one of our user, we will call him "B"

When I send him a e-mai, there is no problem. But when I send him a meeting request, he never receive the invitation. The invitation arrive in a shared mailbox that  user B has access.

There is no rule in is Outlook client.

Can you help me please ?

Thanks in advance.

GenePatton