When installing the HL Accelerator on BizTalk Server 2009, BizTalk Server 2010, or BizTalk Server 2013, the following error occurs:
The specified account "Domain\AccountName" is invalid. Error code: The handle is invalid.
Resolution - Updated August 20
BizTalk 2013 only: Install HL7 using the updated Microsoft BizTalk 2013 Accelerator for HL7.msi file (attached). No updates need to be uninstalled.
Non-BizTalk 2013 versions: If uninstalling 2871997 isn't working, it would be faster to contact the Microsoft BizTalk support team for help. If I hear of another resolution, I will update this post.
This will be documented in KB article 2988484. When this blog post was updated, the KB was not public yet.
This is being investigated by the BizTalk product group. In the meantime, these steps should work if the 2871997 update applies to your server.