Fantastic catch ..I was keep on install and reinstall of sql express and sql management studio.because
My DB contains table and some too from schema.
Same problem..i cant execute query without prefix schema.so i like to go security,logins option and change most time DB Goes inaccessible,I dont know how to get that for that login.what i did in my scenario.
My DB name: CustomerDB
Schema: Customer ,User:Customer,Pswd:*****
1.i attached DB to management studio
2.User folder of CustomerDB contain Customer(user)
3.Mapping schema on both places security ->Login and Security user
4.After that i missed something which is most improtant in my case to avoid schema name.
Final note
That is Uncheck sysadmin in server role..That it..now i run queries without schema..There is no proper references for this case
Thanks once again