I opened a microsoft office 2007 excel file with office 2010 worked on the file and saved the file to a different location. When I closed the file and then tried to reopen it I got the following message "the file you are trying to open".xls" is in
a different format than specified by the file extension. Verify that the file is not corrupted and is from a trusted source before opening the file. do you want to open the file now?" When I choose "yes" the file comes up but with the
message that "macros must be enabled in order to use this workbook".
There is normally there is a box with the option to enable the macros but this doesn't exist on this file. I need to know how to open and use this workbook.