diff --git a/playbook/shopfloor-setup/Shopfloor/lib/Update-MachineNumber.ps1 b/playbook/shopfloor-setup/Shopfloor/lib/Update-MachineNumber.ps1
index fc728c8..d0bb905 100644
--- a/playbook/shopfloor-setup/Shopfloor/lib/Update-MachineNumber.ps1
+++ b/playbook/shopfloor-setup/Shopfloor/lib/Update-MachineNumber.ps1
@@ -163,10 +163,13 @@ function Update-MachineNumber {
         }
         if ($udcSharePath) {
             try {
-                $mountedUdc = Mount-SFLDShare -SharePath $udcSharePath -DriveLetter 'W:'
+                # N:, never W:. GE-Enforce owns W: for its whole cycle, and this
+                # runs as SYSTEM in the same drive namespace - taking W: here kills
+                # the share out from under an in-flight enforce cycle.
+                $mountedUdc = Mount-SFLDShare -SharePath $udcSharePath -DriveLetter 'N:'
                 if ($mountedUdc) {
                     try {
-                        $bayDir   = Join-Path 'W:\' $NewNumber
+                        $bayDir   = Join-Path 'N:\' $NewNumber
                         $srcCur   = Join-Path $bayDir 'CurrentData.json'
                         $srcArc   = Join-Path $bayDir 'ArchivedData'
                         if (Test-Path -LiteralPath $srcCur) {
@@ -226,7 +229,7 @@ function Update-MachineNumber {
                             Write-Host "  Update-MachineNumber: no UDC backup at $bayDir (fresh PC, no prior data)"
                         }
                     } finally {
-                        & net use W: /delete /y 2>$null | Out-Null
+                        & net use N: /delete /y 2>$null | Out-Null
                     }
                 } else {
                     Write-Host "  Update-MachineNumber: UDC backup share unreachable - skipping UDC restore."
diff --git a/playbook/shopfloor-setup/gea-shopfloor-collections/Restore-UDCData.ps1 b/playbook/shopfloor-setup/gea-shopfloor-collections/Restore-UDCData.ps1
index 8fe0088..335d0f3 100644
--- a/playbook/shopfloor-setup/gea-shopfloor-collections/Restore-UDCData.ps1
+++ b/playbook/shopfloor-setup/gea-shopfloor-collections/Restore-UDCData.ps1
@@ -147,7 +147,7 @@ if (-not $mn -or $mn -eq '9999' -or $mn -notmatch '^\d+$') {
 function Mount-SFLDShare {
     param(
         [Parameter(Mandatory)][string]$SharePath,
-        [string]$DriveLetter = 'V:'
+        [string]$DriveLetter = 'R:'
     )
     $server = ($SharePath -replace '^\\\\', '') -split '\\' | Select-Object -First 1
     $basePath = 'HKLM:\SOFTWARE\GE\SFLD\Credentials'
@@ -178,11 +178,18 @@ function Mount-SFLDShare {
     return ($LASTEXITCODE -eq 0)
 }
 
-Log "Mounting share with SFLD creds: $BackupShareRoot -> W:"
+# R:, not W: and not V:. GE-Enforce owns W: for the whole enforce cycle
+# (GE-Enforce.ps1 $driveLetter). This script runs as a manifest PS1 entry
+# inside that cycle, so remapping/deleting W: here kills the share for every
+# later manifest entry - Join-Path on a dead W: returns null and the next
+# entry dies with "Cannot bind argument to parameter 'LiteralPath' because it
+# is null". V: is no good either: Update-MachineNumber.ps1 / Restore-EDncReg.ps1
+# mount V: and run as SYSTEM in the same drive namespace. R: is unclaimed.
+Log "Mounting share with SFLD creds: $BackupShareRoot -> R:"
 $shareMounted = $false
 $sw = [Diagnostics.Stopwatch]::StartNew()
 while ($sw.Elapsed.TotalSeconds -lt $ShareTimeoutSec) {
-    if (Mount-SFLDShare -SharePath $BackupShareRoot -DriveLetter 'W:') {
+    if (Mount-SFLDShare -SharePath $BackupShareRoot -DriveLetter 'R:') {
         $shareMounted = $true
         break
     }
@@ -190,16 +197,16 @@ while ($sw.Elapsed.TotalSeconds -lt $ShareTimeoutSec) {
 }
 $sw.Stop()
 if ($shareMounted) {
-    Log ("Share mounted as W: after {0:N1} s" -f $sw.Elapsed.TotalSeconds)
+    Log ("Share mounted as R: after {0:N1} s" -f $sw.Elapsed.TotalSeconds)
 } else {
     Log "Mount-SFLDShare failed after $ShareTimeoutSec s. SFLD creds may be missing in HKLM:\SOFTWARE\GE\SFLD\Credentials, or the share is unreachable. Exiting non-zero so the dispatcher logs a failure." 'ERROR'
     Log 'Exit 1.'
     exit 1
 }
 
-# All bay-level paths now go through W: (authenticated as SFLD user) so
+# All bay-level paths now go through R: (authenticated as SFLD user) so
 # Test-Path returns the truth, not access-denied-False.
-$bayDir = Join-Path 'W:\' $mn
+$bayDir = Join-Path 'R:\' $mn
 $srcCur = Join-Path $bayDir 'CurrentData.json'
 $srcArc = Join-Path $bayDir 'ArchivedData'
 Log "Probing backup paths for bay $mn"
@@ -213,7 +220,7 @@ Log "  ArchivedData/ src:    $(if ($srcArcExists) { 'present' } else { 'absent'
 
 if (-not $srcCurExists -and -not $srcArcExists) {
     Log "No backup waiting for bay $mn (neither CurrentData.json nor ArchivedData\ at bay root) - no work to do this cycle."
-    & net use W: /delete /y 2>$null | Out-Null
+    & net use R: /delete /y 2>$null | Out-Null
     Log 'Exit 0.'
     exit 0
 }
@@ -251,7 +258,7 @@ if (-not (Test-Path -LiteralPath $UdcDataDir)) {
     } catch {
         Log "Failed to create $UdcDataDir - cannot continue" 'ERROR'
         LogErr $_
-        & net use W: /delete /y 2>$null | Out-Null
+        & net use R: /delete /y 2>$null | Out-Null
         Log 'Exit 1.'
         exit 1
     }
@@ -376,7 +383,7 @@ if ((Test-Path -LiteralPath $UdcExePath) -and ($copiedCur -or $copiedArc)) {
 }
 
 # Unmount the SFLD-creds-mounted drive so we don't leave a stale net-use entry
-& net use W: /delete /y 2>$null | Out-Null
+& net use R: /delete /y 2>$null | Out-Null
 
 Log 'Exit 0.'
 Log '==============================================='