diff --git a/build-windows.ps1 b/build-windows.ps1
index e47ae6d..b57195c 100644
--- a/build-windows.ps1
+++ b/build-windows.ps1
@@ -1,10 +1,10 @@
-# TLS aktivieren
+# TLS aktivieren (Windows Server 2016)
 [Net.ServicePointManager]::SecurityProtocol = `
     [Net.SecurityProtocolType]::Tls12 -bor `
     [Net.SecurityProtocolType]::Tls11 -bor `
     [Net.SecurityProtocolType]::Tls
 
-# Adminrechte pruefen und ggf. neu starten
+# Adminrechte pruefen
 $isAdmin = ([Security.Principal.WindowsPrincipal] `
     [Security.Principal.WindowsIdentity]::GetCurrent() `
 ).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)
@@ -21,13 +21,13 @@ Write-Host " upterm Build-Setup (Go from Source)"
 Write-Host "============================================================"
 Write-Host ""
 
-# Hilfsfunktion: Datei herunterladen mit SSL-Bypass-Fallback
+# Hilfsfunktion: Download mit SSL-Bypass-Fallback
 function Download-File($url, $dest) {
     try {
         (New-Object System.Net.WebClient).DownloadFile($url, $dest)
         return $true
     } catch {}
-    Write-Host "      Standard-Download fehlgeschlagen, versuche SSL-Bypass..."
+    Write-Host "      SSL-Bypass aktiv (Server 2016 Zertifikatskette)..."
     $cb = [Net.ServicePointManager]::ServerCertificateValidationCallback
     [Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}
     try {
@@ -41,33 +41,37 @@ function Download-File($url, $dest) {
     }
 }
 
-# 1. Go pruefen / installieren
+# 1. Go pruefen / als ZIP installieren (kein MSI = kein Exit 1603)
 Write-Host "[1/3] Pruefe Go..."
-$goExe = "C:\Go\bin\go.exe"
+$goRoot = "C:\Go"
+$goExe  = "$goRoot\bin\go.exe"
+
 if (-not (Test-Path $goExe)) {
     $goVersion = "1.22.4"
-    $goMsi    = "$env:TEMP\go-installer.msi"
-    $goUrl    = "https://golang.org/dl/go$goVersion.windows-amd64.msi"
+    $goZip     = "C:\Windows\Temp\go-windows.zip"
+    $goUrl     = "https://golang.org/dl/go$goVersion.windows-amd64.zip"
 
-    Write-Host "      Go nicht gefunden - lade go$goVersion herunter..."
-    if (-not (Download-File $goUrl $goMsi)) {
+    Write-Host "      Go nicht gefunden - lade go$goVersion (ZIP) herunter..."
+    if (-not (Download-File $goUrl $goZip)) {
         Read-Host "Enter zum Beenden"; exit 1
     }
-    Write-Host "      Installiere Go (MSI silent)..."
-    $p = Start-Process msiexec.exe -ArgumentList "/i `"$goMsi`" /quiet /norestart" `
-         -Wait -PassThru
-    if ($p.ExitCode -ne 0) {
-        Write-Host "FEHLER: Go-Installation fehlgeschlagen (Exit $($p.ExitCode))."
+
+    Write-Host "      Entpacke nach $goRoot ..."
+    if (Test-Path $goRoot) { Remove-Item -Recurse -Force $goRoot }
+    Expand-Archive -Path $goZip -DestinationPath "C:\" -Force
+    Remove-Item $goZip -ErrorAction SilentlyContinue
+
+    if (-not (Test-Path $goExe)) {
+        Write-Host "FEHLER: go.exe nach Entpacken nicht gefunden."
         Read-Host "Enter zum Beenden"; exit 1
     }
-    Remove-Item $goMsi -ErrorAction SilentlyContinue
 }
 
 # Go in PATH dieser Session
-if ($env:PATH -notlike "*C:\Go\bin*") {
-    $env:PATH = "$env:PATH;C:\Go\bin"
+if ($env:PATH -notlike "*$goRoot\bin*") {
+    $env:PATH = "$env:PATH;$goRoot\bin"
 }
-$goVer = & "$goExe" version 2>&1
+$goVer = & $goExe version 2>&1
 Write-Host "      OK ($goVer)"
 
 # 2. upterm bauen via go install
@@ -77,7 +81,7 @@ if ($env:PATH -notlike "*$env:GOPATH\bin*") {
     $env:PATH = "$env:PATH;$env:GOPATH\bin"
 }
 try {
-    & "$goExe" install github.com/owenthereal/upterm/cmd/upterm@latest
+    & $goExe install github.com/owenthereal/upterm/cmd/upterm@latest
 } catch {
     Write-Host "FEHLER: go install fehlgeschlagen: $_"
     Read-Host "Enter zum Beenden"; exit 1
@@ -90,15 +94,14 @@ if (-not (Test-Path $uptermExe)) {
 }
 Write-Host "      OK ($uptermExe)"
 
-# 3. Binary systemweit verfuegbar machen
+# 3. Systemweit verfuegbar machen
 Write-Host "[3/3] Kopiere upterm.exe nach C:\Windows\System32..."
 try {
     Copy-Item $uptermExe "C:\Windows\System32\upterm.exe" -Force
     Write-Host "      OK - upterm steht allen Nutzern zur Verfuegung"
 } catch {
-    Write-Host "      Hinweis: Kopieren fehlgeschlagen - upterm ist nur unter:"
-    Write-Host "      $uptermExe"
-    Write-Host "      verfuegbar (PATH-Eintrag manuell noetig)"
+    Write-Host "      Hinweis: Kopieren fehlgeschlagen."
+    Write-Host "      Binary liegt unter: $uptermExe"
 }
 
 Write-Host ""