All, I'm attempting to do a CSV Import of a Custom Record. The Import itself is simple,

InternalId | TextField

I keep getting an error,

That record does not exist.

Has anyone encountered this before? Is there something wrong with my csv format?

If creating a new record via CSV import, don't specify an internal id.

FYI, Internal or External ID is used as the reference key for existing record, that means they are for updates only.

Just to clarify I am doing an Update