Our BB devices were working fine until a couple of days ago, some users cannot send or receive any items and when selecting their Name from BES Manager, it shows "Last Result: Illegal Device PIN".

It policy status for users display "received" where other working devices display "applied successfully".

We are using BES 4.1 with sp1.

Please help!

this means the (PIN) has been placed in a do-not-allow list on the BlackBerry Infrastructure.

How do I fix this?

Contact your service provider.

Supplier does not have a solution. The only thing that seems to work is reactivation of device.

You must select "server" and select the "global" tab . Click on properties and go on "Entreprise Service Policy" , select "PIN" and add your PIN Code .
Retry to activate .. it will be working .

Stoufff