i recently became aware that my 60-GB hard disc had only 3.5 GB of frree space left on it. I installed ODS, and soon found some culprits. However, ODS simply ignored my commands to Delete the culprits. I have got administrator-rights on this MacBook Air (OSX 10.11.6), but apparently that is not enough for ODS, which requires me by some other means to vouch for my privileges. How am i to do that, please ?
Where were the files? If they were in /System or some number of other prevented locations, the files cannot be deleted as they’re in locations protected by macOS itself. Even root cannot delete some files on macOS without disabling system integrity protection (which you should never do).
The most conspicuous candidates were 2 old iNode files, which between them took up more than 11 GB. The location was certainly not protected by OSX, because, when ODS failed to delete them, I deleted them using Finder, Send to Trash, Empty Trash. In that way, I have recovered about 12+ GB.