thank you great man .... the update is successful nowupload the ZIP file "upload-this-to-upgrade-to-2.8.1.zip" to your foodomaa root. NOT extracted files!
After uploaded, right-click "upload-this-to-upgrade-to-2.8.1.zip" -> extract. This will automatically replace the old files.
Then goto: yourdomain/public/auth/login to install upgrade