Error 0x88250009

Value: -2010841079 | 0x88250009 | 2284126217

What does it mean ?

E_RDDB_USER_CONN_PENDING  
This error is returned to RD Connection Broker runtime, when the same user connects to the same farm more than once simultaneously.
Value: 9 | 0x0009 | 0b0000000000001001

Where does it come from ?

FACILITY_RDDB  
Remote Desktop Database
Value: 2085 | 0x825 | 0b100000100101

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