diff --git a/SharePointFunctions.ps1 b/SharePointFunctions.ps1
index 710ee30..8facbe4 100644
--- a/SharePointFunctions.ps1
+++ b/SharePointFunctions.ps1
@@ -482,14 +482,29 @@ function Convert-Files {
                     $workbook = $excel.Workbooks.Open($downloadPath)
                     
                     Write-Host "Saving as XLSX: $xlsxPath"
-                    # Save as XLSX (51 = xlOpenXMLWorkbook)
-                    $workbook.SaveAs($xlsxPath, 51)
+                    # Create a temporary filename without spaces
+                    $tempFileName = [System.IO.Path]::GetRandomFileName() + ".xlsx"
+                    $tempFilePath = Join-Path $env:TEMP $tempFileName
+                    
+                    # Save to temp file first
+                    $workbook.SaveAs([string]$tempFilePath, 51) # 51 = xlOpenXMLWorkbook
                     $workbook.Close($true)
                     
                     Start-Sleep -Seconds 2  # Give Excel time to finish
                     
-                    if (-not (Test-Path -LiteralPath $xlsxPath)) {
-                        throw "Failed to create XLSX file at: $xlsxPath"
+                    # After Excel is closed, rename the file to the desired name
+                    if (Test-Path -LiteralPath $tempFilePath) {
+                        if (Test-Path -LiteralPath $xlsxPath) {
+                            Remove-Item -LiteralPath $xlsxPath -Force
+                        }
+                        Move-Item -LiteralPath $tempFilePath -Destination $xlsxPath -Force
+                        
+                        if (-not (Test-Path -LiteralPath $xlsxPath)) {
+                            throw "Failed to rename temporary file to final XLSX file"
+                        }
+                    }
+                    else {
+                        throw "Failed to create temporary XLSX file at: $tempFilePath"
                     }
                     
                     $script:txtStatus.Text += "Successfully converted to: $xlsxFileName`n"
@@ -504,10 +519,15 @@ function Convert-Files {
                     [System.GC]::Collect()
                     [System.GC]::WaitForPendingFinalizers()
                     
-                    # Kill any remaining Excel processes from this session
+                    # Force cleanup of any remaining Excel processes
                     Get-Process -Name "EXCEL" -ErrorAction SilentlyContinue | 
                         Where-Object { $_.SI -eq [System.Security.Principal.WindowsIdentity]::GetCurrent().SessionId } | 
                         Stop-Process -Force
+                        
+                    # Clean up temp file if it still exists
+                    if ($tempFilePath -and (Test-Path -LiteralPath $tempFilePath)) {
+                        Remove-Item -LiteralPath $tempFilePath -Force -ErrorAction SilentlyContinue
+                    }
                 }
                 
                 $script:txtStatus.Text += "Successfully converted to: $xlsxFileName`n"