A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Either the network your on (Internet) or the person being sent to's network or maybe even some where in-between does not have mime types set correctly.
First make sure that the file has the xls or xlsx extension on the end. each time you save a file in lower left corner should be a check box with show extensions next to it. check that box.
If that don't help. This will a be a guaranteed way to get it there. It will require extra steps on both of your part.
your end:
- locate the save file within Finder: click once to highlight it.
- next from Finder > File Menu > Compress (whatever is the name of the file).
- now when compressed locate that file.
- From your Mail client choose attach locate the compressed file and send.
His end:
- On your other party's end have him save file.
- Then double click on the zip file.
- The file should be intact and he should be able to use it.
This problem is usually caused by a defect in the network software. Or the person responsible either being ignorant of needing to set mime types for the network. Or they knew be were to lazy to do it.