We have a few different environments for dev/test/uat and prod, in the prod environment we have an issue with cached files that never get updated. I have compared the site collection settings for cache between the environments and they are all the same. I have compared the web app settings in web.config and they are the same.
In prod, if I delete a file in a library, empty recycle bin, IIS reset, clear browser cache and all I can still browse to it by pasting the URL, but if I go to the library it is gone (and this even after a few weeks).If I add new files it's fine but if I update a style sheet in the style library and download it (send to ->download a copy) I can see the changes but if I click on it to open it in the browser then it's still the old one.
We're using blob cache storage, could this cause an issue like this? I have never really experienced anything like this before.
Any ideas where to start looking?
Edit: I have tried with adding a random query string after images etc. but still get the old version.