PS close all files after Image processor massive exporting

OK. I always use Batch, not Image Processor, and it never touches open files. Try that instead. 

Not sure I understand what you’re saying.

The whole purpose of the Image Processor is to save the batch of files to the specified location, as an express automated function. You normally don’t want the whole batch to remain open, since that will build up a huge scratch file that could easily choke an average machine, such as, say, a laptop.

If you have other, more special needs, I would recommend File > Automate > Batch, where you could run an action specifically suited for your needs. In the Batch dialog, you can set destination to “None”, leaving it to the action to determine what happens to the processed files (including leaving them open).