If a file is not optimized for more than one user at a time, this indicates: 

Steelhead appliance has entered admission control 

Steelhead appliance is configured with the incorrect speed or duplex on the Primary interface 

Steelhead appliance is configured with the incorrect speed or duplex on the in-path interfaces 

Steelhead appliance is not able to acquire a “File Hold Key (FHK)” 

Steelhead appliance is not able to acquire an “Opportunistic Lock (oplock)” 

Steelhead appliance is not able to acquire a “Double Link (doulink)”