Browsing into 44 IA Upload failures I found 23 cases of probably fixable ones, and 20 cases of unfixable ones.

Among the former I found:

• 14 cases where _jp2.zip file exists, but its prefix is different from IA ID;
• 7 cases where there's no _jp2.zip file, but there's a _tif.zip file;
• 1 case where there's no _jp2.zip file, but there's a _jp2.tar file;
• 1 case where _jp2.zip file exists, but uploader exits with no result (it is a very large item with 1010 pages).

Among the latter (unfixable) I found a variety of abnormal uploads of files (.jpg, .png, .mp3, .ogg...) or of abnormal upload of folders or zip files with name structure different from the allowed one (_images.zip), lacking _djvu.xml file.

My suggestions (unluckily I can't fix code at all....) are:

• to test for existence of a _djvu.xml as first step,
  • if it exists
    • to test for existence of a _jp2.zip file and to use it even if its prefix is different from IA ID
    • if it doesn't exists
      • to test for a _tif.zip file and to use it after a tif to jpg conversion
      • to test for a _jp2.tar file and to use it after a tar splitting

This approach should avoid most fixable IA Uploader failures.