Background image not loading - again!

[maindom]

Hi,
it's an 'again' because i have read through many past posts detailing problems with getting one's own background image to load.
I'm just trying to load a 450x600 (64kb, jpg) image and every time i try i get a 'No file chosen' and the 'Use Background Image?' radio-buttons switch themselves back from Yes to No.
The weird thing is the file/pic is already in the 'public_html....wp-content...background images' directory and the image can be opened / viewed in there. In addition the permissions are set to 777.
I also tried another internet-sourced image - but i don't think it's a copyright block as the original image is from a wikipedia 'commons' article.
I have also tried going in through the WP 'Media' route and added the image that way, but got stuck on what to 'Attach' it to as the background is of course neither a Post or a Page.
Oh - and i already Saved the settings in the Styling tab.
Help please !
Thanks, paul.

Uh - found it, panic over. :-]

[Dan Nickerson]

What is the file name? Does it contain numbers or punctuation? Does it end in .jpg, .gif. .png

Make sure it's a simple name like mybackground.jpg and upload. It will then appear in the background grid, and you need to select it.

Most background issues are either a bad file name, wrong permissions on upload folder or wrong settings in Settings > Media

[maindom]

Thanks Dan,
profuse apologies - it's 20 past midnight here and thus a bad time to be at the site-creation. I left the post up to perhaps stop others being as dim as me - as i hadn't used a background-image before, i was expecting it to appear in the big rectangle right in front of my face above the Select File button. After over an hour and just on giving up, i noticed all the uploads i'd actually conducted nestling in the background GRID below !!! Just looking in the wrong place
At least this might save someone else a wasted hour or two...
Sorry,
Paul.