Word experienced an error trying to open the file

For a variety of reasons, Microsoft Word can sometimes display the following error message when attempting to open older Word documents saved in the Word 97-2003 format (commonly identified by the .doc file extension). This issue, though not necessarily frequent, can be frustrating when working with older file types.

Word experienced an error trying to open the file.
Try these suggestions.
*Check the file permissions for the document or drive.
*Make sure there is sufficient free memory and disk space.
*Open the file with the Text Recovery converter.
C:\Users\<user>\...\filename.doc

To resolve this issue, you will need to follow these steps:

Navigate to File > Options > Trust Center > Trust Center Settings > File Block Settings
If you notice check marks in the rows labeled "Word 2003 Binary Documents and Templates" and/or "Word 2007 Binary Documents and Templates", you should uncheck those boxes, restart Word, and then attempt to open the document again.