MT4- Is this possible to add default comment for every orders?

So save it in a global, use the global in OrderSend. What's the problem?

I think the question is about manual trading?!

Ys. you are right. i ask for manual trading.

I place order manually.

but i use ea to manage the opened trades. ea filter the orders with comment , everytime ea searched the comment and trailing the order.

when i place order manually sometimes i forgot to add comment. i like to avoid these mistakes. Is there any setup in mt4 to save default comment?

No comment needed. Just search for orders with a magic number of zero; those are the manual trades.

Not a good idea, brokers can change comments, including complete replacement.