I have the boards up on my favorite bracket to make it easy to get here and every time I do I get this message. I also get it when I leave the boards up say over night and get up the next morning and click New Posts.
I also get this same message on my phone as well.
Your submission could not be processed because a security token was missing.
If this occurred unexpectedly, please inform the administrator and describe the action you performed before you received this error.