[Yves Dhondt]

What happens if you switch styles? Does it work then? If so, one of the
styles must have been corrupted.

Assuming the above is not the case, display the field code of the in-text
citation: right click on the in-text citation and select "Edit Field...". A
dialog pops up containing something similar to " CITATION Dho07 \l 1033 ".
The "Dho07" part is the tag of the source you are refering to. Verify that
you have a source with that tag in your document. To check if a certain
source is in your document, go to "Manage Sources" and select "Sort by Tag".
The source should be listed on the right. If it isn't, then you are citing a
source which is not available in your document. Check the left column. If
you find the source there, copy it to the right column.

Yves
--
BibWord : Microsoft Word Citation and Bibliography styles
http://bibword.codeplex.com

"francb" wrote in message
...
After adding a new source in the referencing section in a document, I
tried
to cite the source (did it many times successfully in other documents),
but
the message "invalid source" appears. After editing and re-entering the
source, the same problem remains. On the detailed page where the data is
entered everything looks fine. I am using Windows 7, 64bit and Office
2007.