You receive the error message 0x800A175D or -2146822307 when you use Microsoft Office Word as an automation server.
Word is started under a user account whose "user hive" is not loaded. By default, only the interactive user and services running from a user account have their User Registry hive loaded.
Microsoft advises that automation of the Microsoft Office products in this context is not supported.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
257757 Considerations for server-side Automation of Office
To avoid the error, do one of the following:
Start Word as the Interactive User.
Start Word as a user with administrator rights.
Load the user hive for the user account programmatically, or have a dummy service that runs under the user account.
You must identify under what user account Word is running, and in what context you are developing. For example, if you are automating from a Microsoft Transaction Server (MTS) package, the default user account is IWAM_MachineName.
In this scenario, you can change the user to "Interactive User" in the Internet Service Manager Microsoft Management Console, right-click your package, click the Identity tab, and then click Interactive User.
Note MTS might be involved implicitly when automating from ASP. Such an example is when you set your Web application to run in "isolation mode," or when you use Server.CreateObject in Active Server Pages (ASP) code.
In other situations, using the DCOMCNFG.exe utility is appropriate for setting the user under which Word runs.