So I was over in the other thread adding screenshots when I noticed this. I've cut the screenshot to just therelevant part rather than the whole posting page.
I added each image manually by pressing add files, I did 1 at a time, and as I added each, I pressed upload. I did not remove any. Nor did I insert any into the post at any time.
So I added 6 (and only 6) files, but it claims I've used 22 from the 36 available which doesn't even add up to 6x2 (6 images, 6 thumbnails)
In fact as I write this, I have uploaded 1 file, I have not inserted it into the post but it currently claims "Restrictions: 36 per post (19 remaining)" which is just plain weird to me. Note that I had 14 remaining in my previous post to this one which suggests it is not entirely some session holdover.
Pretty obvious at this point the attachment feature is poorly designed, difficult to use, and buggy as a junkyard dog. Is it a major project for someone <hint> to rewrite the core code and fix the bloody thing?
Just noting that I have seen this error too, although it does not happen all the time.
This issue has been logged up on GH:
https://github.com/SimpleMachines/SMF/issues/7486
The problem occurs if your SMF attachment settings (36 in the example above) exceed the php.ini settings (20 in this example). We shouldn't allow the SMF setting to exceed the php.ini setting.
If you're using the upload feature to send the files... surely they're sent ahead of the main payload so you don't hit the $_FILES limit?