This error happens when your site tried to access phpFox Store and at https://store.phpfox.com and failed.
By default, when you access accessing Admin CP, automatically there will be a connection to phpFox Store first to check for app updates, availability...
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As in some cases, store server could be overloaded with requests and result results to a disconnection on your request OR your server has some obstacles while connect connecting to the store server.
Wait a little bit until the connection on the server is stable could solve the issue entirely without any further action.
If the issue continue continues persisting on your phpFox site, we suggest you to contact your hosting provider and ask for the reason why your site server is unable to connect to store server.
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