Problem with Linked Mode / SSO on Vsphere Webclient

Hello,

I have a strange problem, i have 3 Vcenter 5.5 and when i'm trying to connect on the 3rd one with the webclient (login OK), i have an error at loading :

"Unable to connect to Vcenter : wrong credentials on :

https://XXXX1:443/sdk

https://XXXX2:443/sdk

"

And those 2 Vcenter are not availables.

But if i'm connected on the Vsphere Client i have not this problem and access to all 3 Vcenter.

When i'm connected on the Vcenter 1 or 2 with the web client, i have a message : "Unable to connect on Inventory Service on null" but all the 3 Vcenter are available and i can see all data from here.

I don't know where is the problem ... if someone have an idea !

Thanks !

Nico.