I can not play my game because my data is not available.

What must i do to achive this?

And why can i not attach an ordinary jpeg-screenshot?

The forum system only accept lower case in filename extension.
You have to upload *.jpg or *.png, not *.JPG or *.PNG.

It's probably because the poster has less than 7 rep.

https://www.gog.com/forum/general/forum_faqs_new_to_the_forum_click_here/post2

We can't force folks to read stickies labeled "New users should read this", just point them to it.

The poster appears to be playing Witcher 3 if that helps. Or at least that's the only game them have listed in their profile.

I can still not play the Game, because the Game (Cloud synchronisation) does not work. If you mean that depends on my bullshit rep bla points, than i think you have no idea what i'am talking about, isn't it?

Ok, thank you!

I think you have no idea what he's talking about. He was referring to your inability to post attachments being dependent on rep, not to your cloud sync problem.

Also, posting the game name would go a long way in helping us help you.