there was a bug in iRite 1.00 that caused a similar error, Do you have that version installed or have you updated to iRIte 1.0.3?
If you had that version installed, and updated, did you uninstall the previous version before installing iRite 1.0.3? whenever you install a new version of an extesnion you must always uninstall the previous version first.
Was the iRite instance created using 1.0, have you recreated it using 1.0.3?
try editing the iRite instance, on the general Tab, make sure that a skin has been selected, then click OK and upload the WA_iRite folder.