The OK button isn't showing up for me, what's the solution?

 

If this is a MQL5.com Market purchase, it means that you haven't installed it properly, under your MQL5 account.

How to Install your Purchase

Log into your MQL5 account in MT4/5 >> Tools >> Options >> Community. Install the EA only through the Market section:

MT4: Terminal >> Market >> Purchased >> Install

MT5: Navigator >> Market >> My Purchases >> Install

Copying ex4/ex5 files manually will not work for MQL5.com Market purchases. Stay logged into your MQL5 account at all times so the EA continues to run properly.

 
عبدالعزيز الزهراني :
I think you downloaded the demo EA. If you download the demo EA, the OK button won't appear when you attach it to the chart, unless you use backtesting.