(Word export problem) solved: Server exceptions. (The exception comes from hresult: 0 × 80010105 (rpc_e_serverfault ).

Symptom: generate a report in the Word format. During debugging, "server exceptions always occur. (Error from hresult: 0x80010105 (rpc_e_serverfault )"
Cause: Code Wordapp. Documents. Add (ref nothing, ref visible) , The last visibale parameter is set to false.
Solution: visible = true Using System;
Using System. Collections. Generic;
Using System. text;

Namespace Business
{
Public   Class Worddocument
{
Microsoft. Office. InterOP. Word. Application wordapp;
Microsoft. Office. InterOP. Word. Document worddoc;
Object Savechanges =   True ;
Object Visible =   True ; // This is where the problem occurs. If it is set to true, it will run normally.
Object Nothing = System. reflection. Missing. value;
Object Worddocpath;
Public Worddocument ( String Worddocpath)
{
This. Worddocpath=Worddocpath;
This. Open ();
}
Private   Void Open ()
{
If (System. Io. file. exists ( This . Worddocpath. tostring ()))
{
System. Io. file. Delete (This. Worddocpath. tostring ());
}

Wordapp =   New Microsoft. Office. InterOP. Word. applicationclass ();
Worddoc = Wordapp. Documents. Add ( Ref Nothing, Ref Nothing, Ref Nothing, Ref Visible );
}
Public   Void Append ( String Content, Int Level)
{
Worddoc. Paragraphs. Last. range. Text = Worddoc. Paragraphs. Last. range. Text + Content;
Switch (Level)
{
Case   1 :
Worddoc. Paragraphs. Last. range. Font. Bold =   3 ;
Worddoc. Paragraphs. Last. range. Font. Name =   " " ;
Worddoc. Paragraphs. Last. range. Font. Size =   16 ;
Break ;
Case   2 :
Worddoc. Paragraphs. Last. range. Font. Bold =   3 ;
Worddoc. Paragraphs. Last. range. Font. Name =   " " ;
Worddoc. Paragraphs. Last. range. Font. Size =   14 ;
Break ;
Case   3 :
Worddoc. Paragraphs. Last. range. Font. Bold =   3 ;
Worddoc. Paragraphs. Last. range. Font. Name =   " " ;
Worddoc. Paragraphs. Last. range. Font. Size =   12 ;
// Content = "" + content;
Break ;
Default :
Worddoc. Paragraphs. Last. range. Font. Bold =   0 ;
Worddoc. Paragraphs. Last. range. Font. Size =   12 ;
Worddoc. Paragraphs. Last. range. Font. Name =   " " ;
// Content = "" + content;
Break ;
}
// */

}
Public   Void Savedoc ()
{
Worddoc. saveas ( Ref   This . Worddocpath, Ref Nothing, Ref Nothing, Ref Nothing,
Ref Nothing, Ref Nothing, Ref Nothing, Ref Nothing, Ref Nothing, Ref Nothing,
Ref Nothing, Ref Nothing, Ref Nothing, Ref Nothing, Ref Nothing, Ref Nothing );
}
Public   Void Closedoc ()
{
Worddoc. Close (RefSavechanges,RefNothing,RefNothing );
Wordapp. Quit (RefSavechanges,RefNothing,RefNothing );
}
Private   Void Create ( String Worddocpath)
{
System. Io. fileinfo File= NewSystem. Io. fileinfo (worddocpath );
File. Create ();
}
}
}