dual-boot-timesync

Boot-time services that fix hardware clock (RTC) drift when dual-booting Windows and Linux.

The Problem

Windows stores the RTC in local time, Linux stores it in UTC. Each OS "corrects" the clock on boot, leaving the other one wrong by your timezone offset.

The Fix

1. Configure both OSes to treat RTC as UTC
   • Linux: timedatectl set-local-rtc 0
   • Windows: RealTimeIsUniversal = 1 registry key
2. Force immediate NTP sync on boot

Installation

Linux

cd linux/
chmod +x install.sh timesync-fix.sh
sudo bash install.sh

Uninstall: sudo bash install.sh --uninstall

Windows

Open PowerShell as Administrator:

cd windows\
Set-ExecutionPolicy Bypass -Scope Process -Force
.\install.ps1

Uninstall: .\install.ps1 -Uninstall

Logs

• Linux: journalctl -u timesync-fix
• Windows: C:\ProgramData\DualBootTimesync\timesync-fix.log

Troubleshooting

Clock still wrong: Install both sides and reboot into each OS once. Check logs for errors.

Windows "Access denied": Run PowerShell as Administrator.

Linux service fails: Check journalctl -u timesync-fix --no-pager. Common in VMs where timedatectl has no RTC access.