How to drag a local file to specified area of Chrome UI when web testing by TestComplete

To identify the objects in Explorer, you will need to add the property value of WndClass to MSAA in Project Settings. This will expose Explorer objects to TC.

You then need to get the screen coordinates of your Chrome object, in order to move the item from Explorer to your object in Chrome.

If you record your actions, then convert record and playback to scripts, you will be able to see the coding that TC has generated. This will give you an idea, on how to perform drag and drop.