I get the following error which both say the same thing Run-time error (at 150:2448): Error on line 17, position 16 end tag 'nam' does not match the start
Your DLL/EXE.XML files are already corrupted, most likely because you have edited by hand. The installer won't try to touch a corrupted XML, since it will probably destroy it entirely, if it tried to do that. Only you can fix them.
If you don't know how to do it, if you ZIP the files and Attached them on a message (don't copy the text. ZIP the files and attach them to a post), so I can show you the errors.
The XML files are located into
%APPDATA%\Microsoft\FSX
If you use FSX.