Set Enable broker failure to use with SignalR

Hello All.......

I am new in Asp.Net Web development..........

I want to generate database change notification using SignalR, for this, I am using SQL Server 2008 R2.

I am getting failure with following command

ALTER DATABASE SignalRDummy SET ENABLE_BROKER.

It says

"Msg 1205, Level 13, State 68, Line 1
Transaction (Process ID 58) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction.
Msg 5069, Level 16, State 1, Line 1
ALTER DATABASE statement failed."

I have tried

SET DEADLOCK_PRIORITY LOW;

It doesnt work.

Thanks in advance.

Regards.