diff --git a/versionfiles.ps1 b/versionfiles.ps1
index 9f45b5e..f20add9 100644
--- a/versionfiles.ps1
+++ b/versionfiles.ps1
@@ -23,7 +23,7 @@ if (! [string]::IsNullOrEmpty($BuildString)) {
     $verBuildString += " `"-$BuildString`""
 }
 
-$contents=@"
+$NtVerpContents=@"
 #pragma once
 //
 // Generated file: DO NOT EDIT!
@@ -149,12 +149,17 @@ if (!(test-path -path $incPath)) {
 $verpropfile = "$($incPath)\version.props"
 $buildpropfile = "$($incPath)\buildnumber.props"
 [bool] $createdMutex = $false
-[bool] $mutexHeld = $false
 $mutexName = ($incPath -replace "\\","-") -replace ":",""
-$lock = new-object System.Threading.Mutex($false, $mutexName, [ref] $createdMutex);
+$lock = new-object System.Threading.Mutex($true, $mutexName, [ref] $createdMutex);
 try {
-    $mutexHeld = $lock.WaitOne()
+    if (!$createdMutex) {
+        $lock.WaitOne()
+        log "mutex acquired after WaitOne."
+    } else {
+        log "created mutex $mutexName"
+    }
     if ($generateProps -and !(test-path $verpropfile)) {
+        log "creating  $verpropfile"
         $verprops | Set-Content $verpropfile
     }
     [string] $current = ""
@@ -164,26 +169,43 @@ try {
             $current = $current.Trim()
         }
     }
-    $tempContents = $contents.Trim()
+    $tempContents = $NtVerpContents.Trim()
     if (($current.Length -ne $tempContents.Length) -or ($current -cne $tempContents)) {
-        log "creating $($incPath)\ntverp.h"
-        $contents | set-content "$($incPath)\ntverp.h"
+        log "creating $($incPath)\ntverp.h current: $($current.Length) new: $($tempContents.Length)"
+        Remove-Item $incPath\ntverp.h -Force -ErrorAction SilentlyContinue   
+        $tempContents |  Set-Content "$($incPath)\ntverp.h" -Force   
+        $current2 = (get-content "$($incPath)\ntverp.h" -raw)
+        if ($current2.Length) {
+            $current2 = $current2.Trim()
+        }
+        log "New $($incPath)\ntverp.h length  $($current2.Length)"
+        if ($current2.Length -ne $tempContents.Length) {
+            log "Error truncated $($incPath)\ntverp.h now: $($current2.Length)  tempContents: $($tempContents.Length)"
+        }
     }
     if (!(test-path $buildpropfile)) {
         log "creating $buildpropfile"
         $buildNumberProps | Set-Content $buildpropfile
     } else {
-        log "updating $buildpropfile"
-        $buildNumberProps | Set-Content $buildpropfile -Force
+        $current = (get-content  $buildpropfile -raw)
+        if ($current.Length) {
+            $current = $current.Trim()
+        }
+        $buildNumberProps = $buildNumberProps.Trim()
+        if (($current.Length -ne $buildNumberProps.Length) -or ($current -cne $buildNumberProps)) {
+            log "updating $buildpropfile"
+            $buildNumberProps | Set-Content $buildpropfile -Force
+        }
     }
-    $mutexHeld = $false
     $lock.ReleaseMutex()
+    log "mutex released."
 }
 catch {
+    Write-Output $_ | Format-List * -Force | Out-String
 }
 finally {
-    if ($mutexHeld) {
-        $lock.ReleaseMutex();
+    if ($lock) {
+        $lock.Dispose()
     }
 }
 $verfile = "$incPath\version.h"