When converting a geodatabase feature class to a coverage, the following message is produced when the tool completes the conversion:
An error was generated by ArcInfo while executing Layer Export. Would you like to see the output message? Yes No"
Clicking Yes displays the following error, multiple times:
"SHAPE Error(25): Column value could not be converted into a number or date."
This error is displayed at the end:
"ODE sub-process failed"
The geodatabase feature class contains null values in a numeric field. There is no equivalent for this in coverages. Hence, the error message occurs for each occurrence of a null value in the field.
Solution or Workaround
Replace the null values from the geodatabase feature class with a numeric representation for null, before exporting the feature class to a coverage. It's suggested you use zero (0) as the null equivalent.
1. Add the feature class to ArcMap.
2. Open the feature class attribute table and determine which fields contains null values.
3. Click Select By Attributes under the ArcMap Selection menu.
4. Type this query:
[FIELD] is null
Where FIELD is the field containing the null values.
5. Return to the feature class attribute table and make sure only the records containing null values were selected.
6. Right-click the field containing the null values and select Calculate Values from the Options.
7. Type a value into the Field Calculator.
8. Click OK.
This problem has been resolved with ArcGIS 8.1.2.