When I add a k2 item from frontend and try to add an image to the article I get the following error message:

The upload of this file type jpeg is not allowed this website. If you are the server administrator, please add the extensions in the configuraiton in the configuration panel first.

I have the latest K2 version (2.7.0) and I have checked that jpeg and jpg is in the list of allowed MIME (file) types in admin.
Adding images from the backend works fine.

Hello,

The media manager is locked in the frontend, it is only available for browsing. What steps did you take which lead to this error?

Krikor wrote: The media manager is locked in the frontend, it is only available for browsing.

So you're not supposed to be able to add images from the frontend at all? But I know it worked before. The problem started a couple of weeks ago.

Krikor wrote: What steps did you take which lead to this error?

When I login as an administrator from the frontend I have an admin menu that have a link "add new article" (K2 » Artikel edit form). And then, in the article popup, I click at the "Image" button below the editor window. The media manager opens and I try to upload an image, but then the error appears.