If you were using the Windows system and now migrated to Mac system then Keynote application is a great substitute for opening the excel files. But you are facing problem as keynote can't open file that you have created earlier either on Mac or Windows. The possible reason for why this is happening is that may be the file has gone corrupted or the extension of the files has been changed to any other unrecognizable format. You can easily change the extension and resolve keynote can't open file problem but if the corruption has occurred then you have to repair it. Although if you can manage a fresh copy of the file that is not corrupted then the repairing can be ignored and you can restore the file. However when the backup is not available then use the provided iWork recovery software which can repair the keynote file and it can be easily edited and also transferred. The software is very easy to use and powerful too. You just have to scan the drive and damaged files will appear in the preview, select and repair the files you want and they will be restored at given location. This is how easily you can resolve keynote can't open file problem with the help of the software so download it now.