diff --git a/playbook/shopfloor-setup/common/GE-Enforce.ps1 b/playbook/shopfloor-setup/common/GE-Enforce.ps1
index 36b0f2c..cfbad6f 100644
--- a/playbook/shopfloor-setup/common/GE-Enforce.ps1
+++ b/playbook/shopfloor-setup/common/GE-Enforce.ps1
@@ -236,10 +236,19 @@ try {
     # continues if the share path is not writable.
     # ------------------------------------------------------------------
     try {
+        # Re-mount W: before status write-back. Long-running entries (UDC
+        # WaitTimeoutSec=120) can let the SMB session time out idle, leaving
+        # W: as a dead drive letter that fails downstream Path operations
+        # with confusing "argument is null" errors. Cheap to re-attach.
+        & net use $driveLetter /delete /y 2>$null | Out-Null
+        & net use $driveLetter $shopfloorShareRoot /user:$($cred.Username) $($cred.Password) /persistent:no 2>&1 | Out-Null
+
         # Live NetBIOS name from kernel - not $env:COMPUTERNAME, which is
         # cached in the process env block and goes stale after a post-image
         # rename on Intune-managed PCs.
         $hostname   = [System.Environment]::MachineName
+        if (-not $hostname) { $hostname = 'UNKNOWN' }
+        if (-not $driveLetter) { throw 'driveLetter unset before status write-back' }
         $statusDir  = Join-Path (Join-Path $driveLetter '_outputs') (Join-Path 'logs' $hostname)
         if (-not (Test-Path $statusDir)) {
             New-Item -Path $statusDir -ItemType Directory -Force -ErrorAction Stop | Out-Null