Hi - Unless you have an original copy of the file, one guess might be that Excel may have stripped out some of the non-Excel based items. In checking Excel 2003, I didn't see XLA extension support, but Excel add-ins might support this special file format. Below are a few links found in a quick search

http://support.microsoft.com/kb/268016
http://support.microsoft.com/kb/277620
http://www.google.com/search?hl=en&q...ot+save+as+xla