Microsoft is advising users to remove an update for Office 2004 for Mac which was "posted by accident".
The company said in its Security Response Center blog that a pre-release build of a patch had been mistakenly posted as a security update for the MacOS version of Office 2004.
The update contained a general security fix for Office, as well as stability fixes for Entourage and PowerPoint.
According to Microsoft, the update was not a specific fix for the Word vulnerabilities that have seen active exploitation in recent weeks, but rather a general security update.
The company also said that the update was not related to its 12 December Patch Tuesday pre-release.
Microsoft recommends users who have already downloaded and installed the patch to uninstall it. But security organisation SANS warned that removing the patch may not be so simple.
Some users are reporting that the patch cannot be separately uninstalled, and that to remove it users will have to erase and reinstall Office, as well as any desired updates.
Microsoft did not return requests for additional comment from vnunet.com.
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