The .rdr extension is not a native Apple format. In the context of macOS downloads, it usually refers to one of two things:
For the highest security, you should prioritize official Apple sources. However, because 10.13.5 is an older version, finding the exact point release can be difficult. 1. Official Apple Channels (Recommended)
If you download a .rdr file, standard Mac tools like Disk Utility may not open it directly. You will likely need specialized software: Download macOS High Sierra 10.13.5 Update - Apple Support download macos high sierra 10.13.5 image file -.rdr-
: You can find various macOS High Sierra images, including ISO formats , which are useful for virtual machines. How to Use an .rdr Image File
: Formats developed by R-Tools Technology (R-Drive Image) for system recovery and hard disk imaging. Official vs. Unofficial Downloads How to Use an
Apple generally provides the of High Sierra (10.13.6) through its official support pages.
Below is a guide on where to find these files, what the .rdr format entails, and how to safely install macOS High Sierra. Understanding the .rdr File Extension what the .rdr format entails
: Used in communities like ihackinOS to provide a full macOS installation that is bootable immediately once restored to a drive.
If you specifically need a pre-imaged file (like an .rdr ), these are typically hosted on community sites: