Get Older Post Feed

If you mean the feed of your own WordPress blog, it would depend on the number you allowed in Settings > Reading – Syndication feeds show the most recent ___ posts. The same goes for other WordPress blogs, depends on what the Admins set as number of posts.

that means no way to steal feed of older post this way or the other way

Uh, why do you want to steal feed … stealing is bad for the soul.

i know but the reason is not stealing,i created a wordpress blog on free host, i tried every way but the import post function is not working and i have to move my 7350 + posts,Now using article generator (joomla extension) i can grab all full post and post them on my joomla site
but i think theres nothing left for me

“i created a wordpress blog on free host” “but the import post function is not working and i have to move my 7350 + posts”
You do not import, you export your content to move to another application.
Go to WordPress admin dashboard. Tools > Export > All and save the XML file to your computer. I’m sure there are Joomla applications which would help you port

“but i think theres nothing left for me “
Something is getting lost in translation.

i know mate wordpress has tool to export you post which is found as
Tools > Export > All and save the XML file to your computer.
but this is not working in my blog dont know why..i get this error
Problem loading page
Firefox can’t find the file at https://eportals.co.cc/wp-admin/export.php?author=all&submit=Download+Export+File&download=true.

Which free host are you using? Can you re-upload WordPress files/folders just to make sure you’ve got all the files and folders there.

We also have to consider that exporting the XML file size (7350 + posts) might be too huge to process by your free host. I recommend installing Advanced Export for WP & WPMU Plugin where you can export all your posts incrementally by Date Range – Start & end month/year e.g. Jan 2002 to Jan 2003, etc.