import issue while loading users into a custom user account field

Hi,

I created an user account field in Product Category. while loading the users in importer, i am getting the below, i am not sure what should i enter in user account field - name, userid, first name or last name. i tried everything and i am getting the below error -

The object being referred in field IPS_CC_DIRECT_APP to was not found: -2147479248:104:dmnjaqin