an strange error.Broker failed on 1883 but work on 9002

[avayayu]

system:win10 go:1.13

I use hmq as a libary of my projects.But when I config the config.Port = 1883.HMQ always throw error {"level":"error","timestamp":"2020-02-05T15:08:09.637+0800","logger":"broker","caller":"broker/broker.go:191","msg":"Error listening on ","error":"listen tcp :1883: bind: An attempt was made to access a socket in a way forbidden by its access permissions."} But When I config the config.Port = 9002,it works fine.

I am very sure there is no other process listen on port 1883.

So,what's the problem?