How To Update Macos High Sierra 10136 To 1015

If you are still running macOS High Sierra (10.13.6), you are several major releases behind. While High Sierra was a solid performer, it no longer receives security updates from Apple. Upgrading to at least macOS Catalina (10.15) (or newer, like Big Sur, Monterey, or Ventura depending on your Mac model) is critical for security, app compatibility, and new features.

This article provides a complete, safe, and detailed method to upgrade from macOS High Sierra version 10.13.6 to macOS Catalina version 10.15. We will cover prerequisites, compatibility, backup, the upgrade process, troubleshooting, and post-upgrade steps.

Skipping these steps is the number one cause of failed updates and lost data.

Yes, but only if your Mac supports Catalina.
High Sierra (10.13.6) can go directly to Catalina (10.15) via the Software Update pane or the Catalina installer.

Your Mac will restart, show a black screen with an Apple logo and progress bar, then restart again (sometimes twice). This is normal.

Total installation time: 1 to 2 hours (depending on drive speed: SSD = ~45 min, HDD = 1.5+ hours). how to update macos high sierra 10136 to 1015

Some Macs on High Sierra can directly install macOS Big Sur (11) or Monterey (12) without installing Catalina first, provided they meet hardware requirements.

Check your Mac’s maximum supported OS:

To get a newer OS: Search App Store for “macOS Monterey” or “macOS Big Sur.” If the installer allows it, download and run directly from High Sierra. If not, the installer will tell you to update to an intermediate version (Catalina).

Summary

Compatibility and system requirements

Preparation (critical)

The upgrade process (typical path)

Common issues and fixes

Post-upgrade checklist

Pros of upgrading

Cons and tradeoffs

Recommendation

Concise checklist

If you want, I can:

Important Note: The version number you provided (10.13.6) is the final release of High Sierra. There is no version 10.13.136. This guide assumes you meant updating from macOS High Sierra 10.13.6 to macOS Catalina 10.15.x (the immediate successor to Mojave, as High Sierra cannot directly jump to newer OS versions like Ventura or Sonoma on most older hardware). If you are still running macOS High Sierra (10