This issue occurred today while I was trying to run an Ext JS application from IIS, because .json files are not accepted by IIS I tried to add this file extension to the application. But instead I got a 500 error when trying to browse the application.<\/p>\n
After some digging and searching the MIME types section of the website and all other applications, I couldn’t find the conflicting extension.<\/p>\n
I was able to solve the issue by editing the application’s web.config file, right before the mimeMap tag, add a remove tag like following:<\/p>\n
<<\/span>staticContent<\/span>><\/span><\/p>\n <<\/span>remove<\/span> fileExtension<\/span>=<\/span>“<\/span>.json<\/span>“<\/span>\/><\/span><\/p>\n <<\/span>mimeMap<\/span> fileExtension<\/span>=<\/span>“<\/span>.json<\/span>“<\/span> mimeType<\/span>=<\/span>“<\/span>application\/json<\/span>“<\/span> \/><\/span><\/p>\n <\/<\/span>staticContent<\/span>><\/span><\/p>\n I still have no idea why this works, but it works.<\/p>\n","protected":false},"excerpt":{"rendered":" This issue occurred today while I was trying to run an Ext JS application from IIS, because .json files are not accepted by IIS I tried to add this file extension to the application. But instead I got a 500 error when trying to browse the application. After some digging and searching the MIME types … Continue reading “Cannot add duplicate collection entry of type ‘mimeMap’ with unique key attribute ‘fileExtension’ set to ‘.json’”<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[9,13],"class_list":["post-358","post","type-post","status-publish","format-standard","hentry","category-problems","tag-iis","tag-json"],"_links":{"self":[{"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=\/wp\/v2\/posts\/358","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=358"}],"version-history":[{"count":1,"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=\/wp\/v2\/posts\/358\/revisions"}],"predecessor-version":[{"id":359,"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=\/wp\/v2\/posts\/358\/revisions\/359"}],"wp:attachment":[{"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=358"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=358"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bruceng.com\/dev\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=358"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}