When I migrated and copied all the files from the previous server (keeping owner and chmod the same) this still comes up:

Update: Could not open update site #1 "Joomla! Core", URL: https://update.joomla.org/core/list.xml Update: Could not open update site #2 "Accredited Joomla! Translations", URL: https://update.joomla.org/language/translationlist_4.xml Update: Could not open update site #3 "Joomla! Update Component", URL: https://update.joomla.org/core/extensions/com_joomlaupdate.xml Update: Could not open update site #15 "iQuix", URL: https://raw.githubusercontent.com/themexpert/iquix/master/mainfest.xml Update: Could not open update site #16 "Community Builder Package Update Site", URL: https://update.joomlapolis.net/versions/pkg-communitybuilder-list.xml Update: Could not open update site #17 "JMedia Update Site", URL: https://www.themexpert.com/index.php?option=com_digicom&task=responses&source=release&format=xml&provider=joomla&pid=224/extension.xml Update: Could not open update site #18 "Quix Update Site", URL: https://www.themexpert.com/index.php?option=com_digicom&task=responses&source=release&format=xml&provider=joomla&pid=116/extension.xml Update: Could not open update site #19 "Search Update Site", URL: https://raw.githubusercontent.com/joomla-extensions/search/main/manifest.xml Update: Could not open update site #20 "Accredited Joomla! Translations", URL: http://update.joomla.org/language/translationlist_4.xml

I know that PHP 8.1 is having issues, but at least updating to newer Joomla and its Extensions be needed.