JQuery FileUpload + IE8 = Access Denied when trying to upload a file. Turns out the team was styling the file input button to hide the actual file input, but had accidentally given it a width of 1px. The file chooser was working on other browsers because a “choose” event was wired to the actually visible button, which IE couldn’t deal with.
IE8 Caching: IE8 will cache responses with 200 response codes. This can be a problem if your user hits a login-required page, gets a 200 on the response to that, logs in, and attempts to revisit the page. Properly setting cache control headers (which Rails does by default) should fix it.
The Heroku Cedar stack uses Ruby 1.9.2.p290. Just sayin’
IE was giving us “Access is Denied” when using the jQuery fileupload plugin and trying to upload a file. We were styling the file input button in the usual way of hiding the actual file input, but at some point somebody had set the width to 1px. The reason the file picker was still working was somebody had wired a “choose” event to the visible button, which worked in all browsers except IE.