diff --git a/git-hooks/install.ps1 b/git-hooks/install.ps1
index 61071fa..6e6ecb6 100644
--- a/git-hooks/install.ps1
+++ b/git-hooks/install.ps1
@@ -37,5 +37,13 @@ pwsh -NoProfile -NonInteractive -ExecutionPolicy Bypass \
     Write-Host "Installed bash commit-msg hook → $HooksDir"
 }
 
-git config --global core.hooksPath $HooksDir
-Write-Host "Global git hooks path set to: $HooksDir"
+# Git for Windows bash requires POSIX drive notation (e.g. /c/Users/..., not C:\Users\...)
+if ($HooksDir -match '^([A-Za-z]):[/\\](.*)$') {
+    $drive = $Matches[1].ToLower()
+    $rest  = $Matches[2] -replace '\\', '/'
+    $posixHooksDir = "/$drive/$rest"
+} else {
+    $posixHooksDir = $HooksDir -replace '\\', '/'
+}
+git config --global core.hooksPath $posixHooksDir
+Write-Host "Global git hooks path set to: $posixHooksDir"
diff --git a/git-hooks/tests/install.Tests.ps1 b/git-hooks/tests/install.Tests.ps1
index 1fbe42b..d10a29d 100644
--- a/git-hooks/tests/install.Tests.ps1
+++ b/git-hooks/tests/install.Tests.ps1
@@ -29,6 +29,14 @@ Describe 'install.ps1 -UsePowerShell shim' {
         }
     }
 
+    It 'should convert Windows path to POSIX drive notation when setting core.hooksPath' {
+        if ($IsWindows) {
+            $configuredPath = git config --global core.hooksPath
+            $configuredPath | Should -Match '^/[a-z]/'
+            $configuredPath | Should -Not -Match '^[A-Za-z]:'
+        }
+    }
+
     It 'should write the commit-msg shim without a UTF-8 BOM' {
         $shimPath = Join-Path $tempDir 'commit-msg'
         $shimPath | Should -Exist