General Description: When a $FILE parameter is added to a symbol through the Symbol Properties dialog box and the Schematic Editor is closed, the $FILE parameter will disappear when the schematic is reopened.
Solution
The $FILE parameter must be specified in the Symbol Editor.
To do this from the Schematic Editor:
1. Select Tools -> Symbol Editor 2. Use File -> Open to open the symbol 3. Select Symbol -> Parameters 4. Click the "Add" button and enter the $FILE and the desired file name 5. Save the symbol and exit the Symbol Editor
The $FILE parameter will now stay with the symbol on a permanent basis.