Strange errors!

Hello
I am getting a number of incorrect error messages in my aspx.vb file:
1)
')' expected
Using(conn As OleDbConnection = New OleDbConnection(System.Configuration.ConfigurationManager.ConnectionStrings ("usersConnectionString").ConnectionString)) But there is a ')'
2)
Method arguments must be enclosed in parentheses.
.Dim sql = "INSERT INTO userlist (username,password, strEmail) VALUES (@username,@password, @strEmail)" But they are enclosed in parentheses
3)
Method arguments must be enclosed in parentheses.
.Using cmd = New OleDbCommand(sql, conn) Again, they are enclosed in parentheses
4)
'End Using' must be preceded by a matching 'Using'.
End Using There is a preceding 'Using' here: Using(c ...