When I loaded the attached file (3E_dop20rgbi_32379_5686_1_nw.jp2) I got the following error from the latest version of DevIL 1.8.0:
jpc_dec_decodepkts failed
error: cannot decode code stream
I use ilLoadImage(FileName: LPSTR_DL) with the full file name.
Also, the library takes 2 GB of memory during loading of the file.