This command is not available. By writing to Word with Powershell - powershell

Question

My powershell script yesterday stopped working. I have changed nothing in the code or in the path to files. It just stopped working. I can't explain it.
I've tested all path and all variables and its look fine.
function Gen-Doc($Replace, $dataToRaplace, $user_name, $austauch) {
$objWord = New-Object -comobject Word.Application
$objWord.Visible = $false
if ($austauch -eq $true) {
$objDoc = $objWord.Documents.Open("C:\Path\To\Docu\Vorlage\Doc1.docx")
} else {
$objDoc = $objWord.Documents.Open("C:\Path\To\\Docu\Vorlage\Doc2.docx")
}
$objSelection = $objWord.Selection
$n = 0
while ($n -ne $dataToRaplace.Length) {
$FindText = $Replace[$n]
$ReplaceWith = $dataToRaplace[$n]
$MatchCase = $False
$MatchWholeWord = $true
$MatchWildcards = $False
$MatchSoundsLike = $False
$MatchAllWordForms = $False
$Forward = $True
$Wrap = $wdFindContinue
$Format = $False
$wdFindContinue = 1
$wdReplaceAll = 2
$a = $objSelection.Find.Execute($FindText,$MatchCase,$MatchWholeWord, `
$MatchWildcards,$MatchSoundsLike,$MatchAllWordForms,$Forward,`
$Wrap,$Format,$ReplaceWith,$wdReplaceAll)
$n++
}
$filename = $user_name
$objDoc.SaveAs("C:\Path\To\Docu\$filename.docx")
$objWord.Quit()
if ($checkbox2.Checked -eq $true) {
Start-Process -FilePath "C:\Path\To\Docu\$filename.docx" -Verb print
}
}
And here is error message
This command is not available.
At C:\Scripts\Done\Ausgabe.ps1:103 char:9
+ $a = $objSelection.Find.Execute($FindText,$MatchCase,$MatchWh ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : OperationStopped: (:) [], COMException
+ FullyQualifiedErrorId : System.Runtime.InteropServices.COMException

Answer 1

Make sure you don't have your document opened before doing $objDoc.SaveAs.
Check process manager for orphan WINWORD.EXE processes running.