Cannot open 1 Specific Excel attach

I have 1 specific Excel attachment ( sent to me in outlook I can no longer open or save. I get the following message whether I try to open or save
"Cannot create file: Daily Sub sheet - LNA.xls. Right click the folder you want to create the file in, and then click Properties on the shortcut menu to check your permissions with the folder" (Daily Sub sheet - LNA.xls is the name of the file)
However I can save any other attachment to this folder and if I change the folder it gives ne the same error message.
This was a file that was updated daily. No problem until today. And when I go back to previous email and try to open the file with the same name but from a different date same problem when I was able to open it just yesterday. I forwarded the email to my yahoo account and had no problem opening the attachment so it does not appear to be Excel. I have Outlook 2007. The work around is to tell the company to change the name of the file they send me but it seems like this should be easy to fix. Anyone got ideas

And by the way thanks in advance

I tried to "repair" office 2007 but that di not fix anything. In the meantime a new problem surfaced: all Excel97 attachment type files when clicked to open directly without saving, open excel but the file does not load. However I can save them and then open them in Excel. What is going on?