I keep hitting this problem and wanted to capture it on the forum. I have Office 2010 on my machine, but have also installed Visio 2013. Somehow opening or using Visio whacks Flare's ability to connect to Word. Compiling a Word target generates this error:
Compiler (Internal Error): Unable to cast COM object of type 'Microsoft.Office.Interop.Word.ApplicationClass' to interface type 'Microsoft.Office.Interop.Word._Application'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{00020970-0000-0000-C000-000000000046}' failed due to the following error: Library not registered. (Exception from HRESULT: 0x8002801D (TYPE_E_LIBNOTREGISTERED)).
The fix I've found is in this MS article: http://social.msdn.microsoft.com/Forums ... forum=vsto. This references issues with Word 2007 and 2003, but the problem is the same.
The article walks you through finding a TypeLib entry in the registry that is whacked. Once I delete the TypeLib key that is incorrect, Flare is able to compile Word output.
Hope that helps anyone else who's having the problem.
Bob