MS Word Compare problems

We have found there to be a few problems with the Microsoft Word Compare function not working.

There have been a couple of reasons for this.

The first being users upgrading from MS Office 2008 to MS Office 2011. When Office upgrades it does not fully remove the older 2008 suite from a user's computer but leaves elements of it. This causes the compare function to stop working.

To check which version of MS Word your computer is running open AppleScript Editor, located in Applications, Utilities and paste the following:

tell application "Microsoft Word"
return get version
end tell

Press RUN and it'll produce a result like "14.3.8" (a "14.x.x" result means Office 2011 is running, an earlier number means Office 2008 is running).

If it returns a "14.x.x" result open DocMoto and compare two versions in version history. With DocMoto still open go to the Console application in Applications, Utilities. In 'All Messages' the last line should start with a time stamp and say DocMoto Client after it. Expand the message using the triangle to the side. Copy the entire message and then open AppleScript Editor again. Paste the message into AppleScript editor and delete the first line up to the colon ( { date timestamp} DocMoto Client [xxxx]: ).

It should look like this:

tell application "Microsoft Word"
    set oldDocument to POSIX file "/Users/ncameron/Library/DocMoto/connections/localhost/cache/Contents/Projects/A - D/Alpha/Accounting/Alpha Inv 0001.docx/1/Alpha Inv 0001.docx" as text
    open oldDocument
    compare active document path POSIX file "/Users/ncameron/Library/DocMoto/connections/localhost/cache/Contents/Projects/A - D/Alpha/Accounting/Alpha Inv 0001.docx/2/Alpha Inv 0001.docx" as text target compare target selected author name "V1 to V2"
    close document oldDocument
end tell

Run AppleScript Editor. Does MS Word open up the document or is there an error in the Results pane? If Word opens are there any Comparison details on the page?

If the following is returned in Console this brings us to the second possibility.

(date timestamp) DocMotoClient[16411]: error={
    NSAppleScriptErrorAppName = "Microsoft Word";
    NSAppleScriptErrorBriefMessage = "active document doesnU2019t understand the compare message.";
    NSAppleScriptErrorMessage = "Microsoft Word got an error: active document doesnU2019t understand the compare message.";
    NSAppleScriptErrorNumber = "-1708";
    NSAppleScriptErrorRange = "NSRange: {502, 453}";

This is down to a mixture of the length of DNS name, user's name and path to the file being over 256 characters that Microsoft Word compare cannot deal with.

This combination will make the ultimate comparison string over 256 characters and MS Word compare will fail.

To prove this connect using the DocMoto's server IP address rather than a DNS name with a user with a shorter name to a file that is in a folder just off the root and compare two versions, so the comparison string for version 1 and 2 of a file would look something similar to this:



Our engineers are looking to reduce the possibility of this second issue happening, however there will always be the possibility of a long path somewhere in your system. The solution when this occurs is to reduce the path length by either renaming the file or its parent folders, or simply moving the file.

Visual Basic error when trying to compare documents.


This is usually caused by badly installed MS Word.

The solution is to follow the steps in to completely uninstall and then reinstall MS Office. You should then be able to successfully run a MS Word comparison.

The following is not a defect of DocMoto, but some DocMoto users with Parallels and Office 365 could be affected.

If you have an Office 365 subscription and have installed both the Mac and Windows versions of Office, installing the Windows version inside Parallels virtual machine disables DocMoto's comparison feature. If you run the AppleScript above that returns the word version number instead of returning a number, it returns the name of the Parallels virtual machine.

The solution, with the virtual machine shut down, is go to the Virtual Machine menu in parallels and select “Configure.” Under the options tab, with the Applications entry selected, uncheck “Share Windows Applications with Mac”.

A screen shot of the relevant option in Parallels follows.


Still have a question?

If you still can't find the answer to your question or need more information, please contact the DocMoto team on +44 (0)1242 225230 or email us

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