When download is finishing, IDM shows error message that it cannot rebuild temporary files. Why can this happen?

Usually this error occurs if a temporary file is used by some other application. It can be some FireWall/Antivirus/InternetSecurity application for example, which controls traffic and all files (file parts) that are written on disk. Please try to restart your computer and then resume the download. In most cases, IDM will rebuild the temporary files.

Also it can happen if you do not have enough free space on your hard drive. Please free some space and try to resume the download.