Hi Martin,
The file doesn't contain any color formatting. It does contain bold & underline text formatting within the four line header information however. Have removed these formattings and no change in that Fox still closes down. Have removed all four lines of header info and still the same!
The sheet has frozen panes but this will will not prevent a straight append. Likewise, have tested to ensure their are no issues with long files names on XLS files and this doesn't appear to be the issue either.
All I can presume is that there is some sort of column/sheet formatting which is causing a conflict somewhere. Very strange!
Regards
Jeff