RPC Error in Point of Sale Submit Account & Postman DB Not available error

RPC ERROR POINT OF SALE SUBMIT ACCOUNT AND POSTMAN DATABASE NOT AVAILABE ERROR.

WHILE TAKING THE POSTMAN RETURNS OPTION IN TREASURY IF AN ERROR 

"POSTMAN DATABASE NOT AVAILABE" COMES

PL.RUN THE FOLLOWING QUERY FOR RPC. REPLACE" MYSERVER" WITH YOUR SERVER NAME.

THIS QUERY CAN BE USED FOR RPC ERROR COMES WHILE DOING SUBMIT ACCOUNT IN POINT OF SALE ALSO.

exec sp_serveroption @server='MYSERVER', @optname='rpc', @optvalue='true'
go
exec sp_serveroption @server='MYSERVER', @optname='rpc out', @optvalue='true'
go

RPC Error in SQL 2008