Hi,
I use K2 2.5.7 with Joomla 2.5.4.
I uploaded an attachment in an Item and tested from the front-end to see if it was downloadable and not corupted, unfortunatly the images ( jpg, gif, etc.. ) became corupted after inserting them into K2 and therefore not viewable after download.
this issue was also known in earlier version of K2 see this article:
getk2.org/community/New-to-K2-Ask-here-first!/9506-Problems-with-uploading-attachments-files
Please fix this and if some one knows how I'm dying to hear how. The solution in the above mentioned article is not actual anymore for this version of K2