I was having that problem however deleting cookies didn't help had the issue on my desktop, my phone and my laptop as well as my work computer have no clue why but it just stated working again this morning.
Is it possible that this happens as the result of temp bans which they are not informing us of? i know the day before mine got all messed up i said some rather rude things regarding someone who proudly posted videos of him hacking on this site.
Thanks OP. Never throught of trying that, but it seems to actually work. Seems like the forums here need about as much work as the game. I actually went on quite a tangent over at the Steam forums the other night after I tried to post some issues here, but couldn't reply, or open any new topics. Still I would recommend to every one to copy your post into the clipboard before clicking the submit button. Your post might just go missing.