Can’t upload images.

Hi everyone.
I’m new at this and i need a step-by-step guide, cause i’m not a tech-guy!

Everytime i try to upload an image in a post a get stuck. I choose add image, i browse and find my image file, and then…. white screen. No upload now button, or OK or anything.

I’ve spent roughly two hours now digging my way through the forum and nobody has an answer, so i’ll ask again:

How do i upload an image? And please – explain it to me as i was a 6 year old!!!!