Upgrade fail

Hi, After trying to upgrade to 1.18, i got the following error: An AJAX HTTP error occurred. HTTP Result Code: 200 Debugging information follows. Path: http://kundanitraining.co.za/update.php?op=selection&token=VkzDTddc0ESn… StatusText: OK ResponseText: Requirements problem | Kundani LMS 2015-2016 @import url("http://kundanitraining.co.za/modules/system/system.base.css?nlrp6p"); @import url("http://kundanitraining.co.za/modules/system/system.admin.css?nlrp6p"); @import url("http://kundanitraining.co.za/modules/system/system.menus.css?nlrp6p"); @import url("http://kundanitraining.co.za/modules/system/system.messages.css?nlrp6p"); @import url("http://kundanitraining.co.za/modules/system/system.theme.css?nlrp6p"); @import url("http://kundanitraining.co.za/modules/system/system.maintenance.css?nlrp…"); @import url("http://kundanitraining.co.za/themes/seven/reset.css?nlrp6p"); @import url("http://kundanitraining.co.za/themes/seven/style.css?nlrp6p"); Requirements problem Installation tasksVerify requirements(active)OverviewReview updatesRun updatesReview log WarningFileinfoNot presentThe h5peditor module requires this php extension to properly check the mime type of uploaded files. If the extension isn't present browser input will be used.OKWeb serverApacheOKPHP5.3.29OKPHP register globalsDisabledOKPHP extensionsEnabledOKDatabase supportEnabledOKPHP memory limit256MOKFile systemWritable (public download method)OKUnicode libraryPHP Mbstring ExtensionCheck the error messages and try again. how can i remedy this