I have an old excel template file (2003?) in our vault and someone wants to make update the file.  As soon as we check it out, the file changes from an .xlt file to an .xlsx file and adds "1" to the file name.  I would change the file by selecting the extension but the extensions won't show up even when I go into windows and modify it to show all extensions.  I also tried to overwrite the file but that won't work since the original file doesn't show up when I try to do a save as, even with changing the file type to any of the template options.

I don't want to just delete the old file because of the history and I prefer not to start a new file and move the old file into an obsolete folder.

Any ideas?

Thanks;

Stephen