If you used the IFX the extraction is likley inline and should be easy to edit via the UI. Got to Manager > Fields > Field extractions and click on the name of the field extraction you created in the IFX. In the Extract/Transform field hunt down the field name (it will look similar to this: (?P
Alternatively, you can edit the appropriate EXTRACT line in the appropriate props.conf configuration file in $SPLUNK_HOME$/etc/apps/yourapp/local/props.conf.
Spoke too soon. I had tried renaming the field in props.conf. After your answer I renamed it back to the original name and then tried to delete the field using Manager > Fields > Field extractions but kept getting an error. So I renamed props.conf to xprops.conf hoping to get rid of it that way. However when I run a search I still see the original field name and my attempted renaming of it in the list of fields.
No fields appear in Manager > Fields > Field extractions
The only props.conf that contained the field name in question was in:
I had tried renaming the props.conf file thinking that I could then recreate the field spelled correctly, but it seemed to have no effect. I can still find no way to either delete the field so that it can be recreated, or to edit its contents unless I modify the generated regular expression manually.