Issues with Excel 2003 files

Dear Experts, please can you help?
When I create Excel documents using Excel 2003 on my Windows 7 system it saves them as 'OOBE.' documents.
If I try to open them from 'My Computer' it says it cannot open them (the Open With option does not suggest Excel). However if I open Excel first then go File Open, then document is fine.
When attaching these files to emails they don't look like Excel files then either.
Many thanks,
Jaspeee

Try installing the Microsoft Office Compatibility Pack alongside Office 2003, also, have you tried right-clicking the relevant documents and selecting Open With?

Microsoft Office Compatibility Pack for Word, Excel and PowerPoint 2007 - Microsoft Digital Life New Zealand

Thanks for the reply seavixen32. I'll try that.
Jaspeee