InDesign Publish Online tells me sources are missing (?), if I proceed uploading I get error #13

(Sorry, the error is in Dutch. It says

Sourc(es):  8 missing

   No memory available)

Every time I try to upload my InDesign file, containing over several 3 short videos and links to Illustrator pages, it gives me this error. If I click to proceed with publishing my document, it gives me error #13.

When I try to do what this forum has told me I get different errors or it doesn't help at all.

Thanks in advance.