What could cause a "command failed" error when using the Word.Application object to compare two documents?

Question

I have two word documents that are a "result" of a test and an "expected result". I'm using the following code to compare the two and check for differences.

Sub CompareTest 
  Dim wrdApp 
  Dim revTemp 
  Dim file1, file2, differences 
  Set wrdApp = Sys.OleObject("Word.Application") 
  file1 = "C:\TestDocs\Site Initiation.doc"   
  file2 = "C:\TestDocs\Site Initiation_observer.doc" 
  differences = "C:\TestDocs\differences.doc" 
  call wrdApp.Documents.Open(file1)  
  call wrdApp.ActiveDocument.Compare(file2, "", 1)   
  Set revTemp = wrdApp.Selection.NextRevision(True) 
  If Not (revTemp Is Nothing) Then 
    wrdApp.ActiveDocument.SaveAs differences  
    wrdApp.Documents.Close 
    Call Log.Warning "Documents are not identical", "Please see the differences in " & differences  
  Else 
    Call Log.Message "Documents are identical"    
  End If 
  wrdApp.Quit False 
End Sub

For whatever reason, for most of the word documents we're comparing like this, everything works fine. However, for two of them we're comparing, we're getting "Command Failed" on the line that is calling the "Compare" method.

I've searched Microsoft's library on line, numerous blogs, etc., and no one can give me a specific situation where this code would work for MOST documents but not for certain scenarios. I've tried reversing the order of the documents, changing the document names and the directory paths to be more compatible with an 8.3 format. I've tried comparing each document to itself as well.

A little help would be greatly appreciated.

FYI, this is code being run in the TestComplete automated testing tool so the specifics of "Sys.OleObject" and the "Log" object are internal to that tool. We've used "CreateObject" and commented out the Log calls to no avail.

Answer 1

My transcribed debugging session is below - the short answer is that Compare will fail if there are unaccepted revision changes in the comparison document.

Details:

Here are some clues and potential answers.

1. I reproduced the error
2. I made a copy of the first doc and compared it with itself – that worked.
3. I made a copy of the second file and compared it with itself – that reproduced the command failed error
4. I tried comparing the docs from step3 (…observation.doc) manually from word. It worked, but I had to confirm that it was ok to compare against tracked changes
5. Based on the above, I accepted all changes and saved the original doc, then reran the comparison – it worked!

So – it has something to do with the unaccepted changes to the doc.

My final experiment was to take a simple doc, turn on track changes, make some edits, then save without accepting. I compared this doc with itself and reproduced the error (command failed).

My advice: save the unaccepted changes before comparing (you can probably use Document.AcceptAllRevisions from the script if you want to).

Answer 2

Created an automated appliction (.exe) to generate word document by using windows schedular we are calling the .exe file for every 1 hour.

while saving (saveas) throwing an error message "Command failed", if it is executed by using windows scheduler(selected even user logged off the system option).

Not throwing an error (creating the document successfully) by manually executing the .exe file.