About Arbortext Styler > Extending Stylesheets > Editing FOSI Source of Elements with Numbered Contexts or Conditions
  
Editing FOSI Source of Elements with Numbered Contexts or Conditions
If you edit source of an element that includes contain numbering definitions for any of its contexts or conditions, and then subsequently remove the numbering from that context or condition, you must return to the edited source and make the necessary changes to update the numbering. The generated text function does not extend into edited source to search for and remove deleted numbering definitions so the stylesheet will generate errors on document open or preview until the edited source has been fixed:
[A28138] Stylesheet has references to missing definitions.
These references will be ignored, use Styler's Validate
Stylesheet menu item to locate these errors.
However, the Tools > Validate Stylesheet option also does not extend into edited source and hence you will need to use a different method of error detection to find out the cause of the problem:
1. Export the stylesheet in FOSI format to an external file, via the File > Export > FOSI menu option.
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Your stylesheet must be set to use FOSI as the print/PDF engine to access this menu option.
2. In Arbortext Editor, select the exported FOSI as the stylesheet for the document.
3. View the completeness errors that are reported by Arbortext Editor/Arbortext Styler when the stylesheet change is made.
4. Locate and edit the erroneous numbering definitions directly in the FOSI source: open the exported FOSI in Arbortext Editor, then use the Tools > IDs and ID References tool to locate the particular definition causing the error.