The information in this article applies to:
Whenever I try to open a particular plan file, an error message states,
"Unable to open the file", followed by the file's name.
What am I doing wrong?
This error message indicates that although the file has a file extension recognized by the software, the contents of the file are such that the file cannot be read. There are a couple of possible reason for this:
If the file in question has been renamed, it is best that you restore its original file extension. Changing a file's extension does not change its file type or allow different applications to read it. In fact, it may prevent applications that should be able to read the file from doing so.
If the file is missing data, there is most likely nothing that can be done to recover it. You will need to resume work by opening and renaming a copy of your most recent backup.
While there are no guaranteed ways to always prevent file corruption, here are a few tips to help avoid missing data in the future: