Add any of these class names to display the category icon. .apicon-dots .apicon-check .apicon-chevron-down .apicon-chevron-up .apicon-chevron-right .apicon-chevron-left .apicon-file-image-o .apicon-file-excel-o .apicon-file-code-o .apicon-file-movie-o .apicon-file-audio-o .apicon-file-archive-o .apicon-file-word-o .apicon-file-pdf-o .apicon-file-text-o .apicon-file-powerpoint-o .apicon-google-plus-square .apicon-twitter-square .apicon-facebook-square .apicon-toggle-on .apicon-toggle-off .apicon-image .apicon-category .apicon-tag .apicon-comments .apicon-anspress .apicon-anspress-icon .apicon-flag .apicon-answer .apicon-question .apicon-home .apicon-thumbs-up-down .apicon-thumb-up .apicon-thumb-down .apicon-pencil .apicon-users .apicon-user-check .apicon-user-minus .apicon-user-plus .apicon-user .apicon-profile .apicon-reputation .apicon-screen-normal .apicon-screen-full .apicon-alert .apicon-bug .apicon-calendar .apicon-clock .apicon-cloud-upload .apicon-ellipsis .apicon-eye .apicon-gear .apicon-gist-secret .apicon-globe .apicon-heart .apicon-link .apicon-lock .apicon-mail .apicon-mail-read .apicon-mark-github .apicon-mention .apicon-mortar-board .apicon-mute .apicon-pin .apicon-plus .apicon-pulse .apicon-puzzle .apicon-rss .apicon-search .apicon-star .apicon-stop .apicon-sync .apicon-trashcan .apicon-x .apicon-board

I don’t know, why is this error keep coming. As mentioned in the error, I retried but after a few minutes, it came again 🙁  

Hello Atul, I replied to your questen yesterday but its look like it got deleted while doing maintenance in our site. You can simply visit: YOURSITE.com/wp-admin/admin.php?page=anspress_upgrade and follow upgrade process.