Format get lost in excel file

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What steps will reproduce the problem?
1. Open an excel file that has formatted text using CompoundDocument.Open
2. Save it with a different name. All the format was lost

I expected that the format were kept.

The same happened when I set a bold font programmatically and then saved
the file. Format is not taken into account

The version of the product is of 03/31/2009

```

Original issue reported on code.google.com by `soported...@gmail.com` on 28 Jul 2009 at 9:29

Start by reproducing the issue with CompoundDocument.Open: open a formatted Excel file, save it under a different name, and verify whether formatting is lost. Also test a programmatically applied bold font; the work is done when both existing and newly assigned formatting survive the save.

Written by the indexing model from the issue text.