diff --git a/setup-windows.ps1 b/setup-windows.ps1
index d44d874..599b235 100644
--- a/setup-windows.ps1
+++ b/setup-windows.ps1
@@ -156,6 +156,19 @@ if (-not (Get-Command upterm -ErrorAction SilentlyContinue)) {
 }
 Write-Host "      OK"
 
+# 5. SSH-Key generieren (benoetigt fuer upterm-Authentifizierung)
+Write-Host "[5/5] Pruefe SSH-Key..."
+$sshDir = "$env:USERPROFILE\.ssh"
+$keyFile = "$sshDir\id_ed25519"
+if (-not (Test-Path $keyFile)) {
+    Write-Host "      Kein SSH-Key gefunden - generiere ed25519-Key..."
+    if (-not (Test-Path $sshDir)) { New-Item -ItemType Directory -Path $sshDir | Out-Null }
+    ssh-keygen -t ed25519 -f $keyFile -N '""' -q
+    Write-Host "      SSH-Key erstellt: $keyFile"
+} else {
+    Write-Host "      SSH-Key bereits vorhanden."
+}
+
 Write-Host ""
 Write-Host "============================================================"
 Write-Host " Installation abgeschlossen!"