Whats the minimum Expiration time possible?

[Forex Trader]

I have this piece of code:

OrderModify(Ticket, Entry, SL, TP, Expiration, CLR_NONE);

I tried a large Expiration number and it works; when I tried a smaller Expiration, it wont work.

[Forex Trader]

F1 - Trading - Trade Positions - Placing of Pending Orders
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Attention: Order may not expire earlier than in 10 minutes!
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